fixes to source-pane accessibility

- make document outline view aria-hidden when visibly hidden
- annotate document outline view splitter
- initial wiring for command to speak editor status
- mark various source pane tabpanels with correct role, and give them labels (text editor, object explorer, code browser, data viewer, url viewer. profile results)
-

src/gwt/src/org/rstudio/core/client/a11y/A11y.java

@@ -1,7 +1,7 @@
 /*
  * A11y.java
  *
- * Copyright (C) 2009-19 by RStudio, Inc.
+ * Copyright (C) 2009-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -102,6 +102,15 @@ public static void setARIAHidden(Element el)
       el.setAttribute("aria-hidden", "true");
    }
 
+   /**
+    * Make an element visible to screen readers.
+    * @param el
+    */
+   public static void setARIAVisible(Element el)
+   {
+      el.removeAttribute("aria-hidden");
+   }
+
    public static void setVisuallyHidden(Widget widget)
    {
       setVisuallyHidden(widget.getElement());

src/gwt/src/org/rstudio/core/client/widget/AriaLiveStatusWidget.java

@@ -1,7 +1,7 @@
 /*
  * AriaLiveStatusWidget.java
  *
- * Copyright (C) 2019 by RStudio, Inc.
+ * Copyright (C) 2019-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -36,21 +36,24 @@ public void announce(String message, int speakDelayMs)
    {
       if (speakDelayMs < 0)
       {
-         if (updateReaderTimer_.isRunning())
-            updateReaderTimer_.cancel();
+         clearMessage();
          return;
       }
 
       resultsMessage_ = message;
       if (updateReaderTimer_.isRunning())
          updateReaderTimer_.cancel();
+      if (clearReaderTimer_.isRunning())
+         clearReaderTimer_.cancel();
       updateReaderTimer_.schedule(speakDelayMs);
    }
 
    public void clearMessage()
    {
       if (updateReaderTimer_.isRunning())
          updateReaderTimer_.cancel();
+      if (clearReaderTimer_.isRunning())
+         clearReaderTimer_.cancel();
       getElement().setInnerText("");
    }
 
@@ -63,8 +66,23 @@ public void clearMessage()
       public void run()
       {
          getElement().setInnerText(resultsMessage_);
+         if (clearReaderTimer_.isRunning())
+            clearReaderTimer_.cancel();
+         clearReaderTimer_.schedule(4000);
       }
    };
 
+   /**
+    * Timer for clearing the previous message if nothing new arrives
+    */
+   private Timer clearReaderTimer_ = new Timer()
+   {
+     @Override
+     public void run()
+     {
+        getElement().setInnerText("");
+     }
+   };
+
    private String resultsMessage_;
 }

src/gwt/src/org/rstudio/studio/client/application/Application.java

@@ -351,7 +351,7 @@ public void onFileUpload(FileUploadEvent event)
    @Override
    public void onAriaLiveStatus(AriaLiveStatusEvent event)
    {
-      int delayMs = userPrefs_.get().typingStatusDelayMs().getValue();
+      int delayMs = event.getImmediate() ? 0 : userPrefs_.get().typingStatusDelayMs().getValue();
       if (!ModalDialogTracker.dispatchAriaLiveStatus(event.getMessage(), delayMs))
          view_.reportStatus(event.getMessage(), userPrefs_.get().typingStatusDelayMs().getValue());
    }
@@ -1012,6 +1012,12 @@ else if (!sessionInfo.getShowIdentity() || !sessionInfo.getAllowFullUI())
          commands_.importDatasetFromXLS().remove();
       }
 
+      // remove commands that only make sense if screen reader is enabled
+      if (!userPrefs_.get().enableScreenReader().getValue())
+      {
+         commands_.speakEditorLocation().remove();
+      }
+
       // If no project, ensure we show the product-edition title; if there is a project
       // open this was already done
       if (!Desktop.isDesktop() &&

src/gwt/src/org/rstudio/studio/client/application/events/AriaLiveStatusEvent.java

@@ -1,7 +1,7 @@
 /*
  * AriaLiveStatusEvent.java
  *
- * Copyright (C) 2019 by RStudio, Inc.
+ * Copyright (C) 2019-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -25,14 +25,25 @@ public interface Handler extends EventHandler
    }
 
    public AriaLiveStatusEvent(String message)
+   {
+      this(message, false);
+   }
+
+   public AriaLiveStatusEvent(String message, boolean immediate)
    {
       message_ = message;
+      immediate_ = immediate;
    }
 
    public String getMessage()
    {
       return message_;
    }
+
+   public boolean getImmediate()
+   {
+      return immediate_;
+   }
 
    @Override
    protected void dispatch(AriaLiveStatusEvent.Handler handler)
@@ -47,6 +58,7 @@ public Type<AriaLiveStatusEvent.Handler> getAssociatedType()
    }
 
    private final String message_;
+   private final boolean immediate_;
 
    public static final Type<AriaLiveStatusEvent.Handler> TYPE = new Type<>();
 }

src/gwt/src/org/rstudio/studio/client/common/satellite/SatelliteWindow.java

@@ -1,7 +1,7 @@
 /*
  * SatelliteWindow.java
  *
- * Copyright (C) 2009-19 by RStudio, Inc.
+ * Copyright (C) 2009-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -144,7 +144,7 @@ public void onResize()
    @Override
    public void onAriaLiveStatus(AriaLiveStatusEvent event)
    {
-      int delayMs = RStudioGinjector.INSTANCE.getUserPrefs().typingStatusDelayMs().getValue();
+      int delayMs = event.getImmediate() ? 0 : RStudioGinjector.INSTANCE.getUserPrefs().typingStatusDelayMs().getValue();
       if (!ModalDialogTracker.dispatchAriaLiveStatus(event.getMessage(), delayMs))
          ariaLiveStatusWidget_.announce(event.getMessage(), delayMs);
    }

src/gwt/src/org/rstudio/studio/client/workbench/commands/Commands.cmd.xml

@@ -502,6 +502,9 @@ well as menu structures (for main menu and popup menus).
             <cmd refid="toggleScreenReaderSupport"/>
             <cmd refid="toggleTabKeyMovesFocus"/>
             <separator/>
+            <menu label="Speak">
+               <cmd refid="speakEditorLocation"/>
+            </menu>
             <cmd refid="focusMainToolbar"/>
             <separator/>
             <cmd refid="showAccessibilityOptions"/>
@@ -828,6 +831,7 @@ well as menu structures (for main menu and popup menus).
          <shortcut refid="projectOptions" value="Shift+Meta+," if="org.rstudio.core.client.BrowseCap.isMacintosh()"/> 
          <shortcut refid="goToHelp" value="Ctrl+C Ctrl+V" disableModes="default,vim,sublime"/>
          <shortcut refid="toggleTabKeyMovesFocus" value="Ctrl+Alt+Shift+T"/>
+         <shortcut refid="speakEditorLocation" value="Ctrl+Shift+B"/>
       </shortcutgroup>
       <shortcutgroup name="Console">
          <shortcut refid="consoleClear" value="Ctrl+L" disableModes="emacs"/>
@@ -3621,4 +3625,8 @@ well as menu structures (for main menu and popup menus).
         menuLabel="Sign Ou_t"
         desc="Sign out from RStudio"
         windowMode="main"/>
+
+   <cmd id="speakEditorLocation"
+        menuLabel="Speak Text Editor Location"
+        windowMode="main"/>
 </commands>

src/gwt/src/org/rstudio/studio/client/workbench/commands/Commands.java

@@ -640,6 +640,7 @@
    public abstract AppCommand toggleTabKeyMovesFocus();
    public abstract AppCommand showAccessibilityOptions();
    public abstract AppCommand focusMainToolbar();
+   public abstract AppCommand speakEditorLocation();
 
    // Internal
    public abstract AppCommand showDomElements();

src/gwt/src/org/rstudio/studio/client/workbench/views/source/DocumentOutlineWidget.css

@@ -30,7 +30,7 @@
    overflow: hidden;
    margin-top: 20px;
    font-style: italic;
-   color: rgb(128, 128, 128) !important;
+   color: rgb(117, 117, 117) !important;
 }
 
 .tree {

src/gwt/src/org/rstudio/studio/client/workbench/views/source/DocumentOutlineWidget.java

@@ -1,7 +1,7 @@
 /*
  * DocumentOutlineWidget.java
  *
- * Copyright (C) 2009-12 by RStudio, Inc.
+ * Copyright (C) 2009-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -14,10 +14,13 @@
  */
 package org.rstudio.studio.client.workbench.views.source;
 
+import com.google.gwt.aria.client.OrientationValue;
+import com.google.gwt.aria.client.Roles;
 import org.rstudio.core.client.CommandWithArg;
 import org.rstudio.core.client.Counter;
 import org.rstudio.core.client.HandlerRegistrations;
 import org.rstudio.core.client.StringUtil;
+import org.rstudio.core.client.a11y.A11y;
 import org.rstudio.core.client.dom.DomUtils;
 import org.rstudio.core.client.theme.res.ThemeStyles;
 import org.rstudio.studio.client.RStudioGinjector;
@@ -63,6 +66,9 @@ public VerticalSeparator()
       {
          panel_ = new FlowPanel();
          panel_.addStyleName(RES.styles().leftSeparator());
+         Roles.getSeparatorRole().set(panel_.getElement());
+         Roles.getSeparatorRole().setAriaOrientationProperty(panel_.getElement(),
+               OrientationValue.VERTICAL);
          initWidget(panel_);
       }
 
@@ -228,6 +234,7 @@ public DocumentOutlineWidget(TextEditingTarget target)
 
       tree_ = new Tree();
       tree_.addStyleName(RES.styles().tree());
+      Roles.getTreeRole().setAriaLabelProperty(tree_.getElement(), "Document Outline");
 
       panel_ = new FlowPanel();
       panel_.addStyleName(RES.styles().panel());
@@ -252,6 +259,14 @@ public void onEditorThemeStyleChanged(EditorThemeStyleChangedEvent event)
       updateStyles(emptyPlaceholder_, event.getStyle());
    }
 
+   public void setAriaVisible(boolean visible)
+   {
+      if (visible)
+         A11y.setARIAVisible(getElement());
+      else
+         A11y.setARIAHidden(getElement());
+   }
+
    private void initHandlers()
    {
       handlers_.add(target_.getDocDisplay().addScopeTreeReadyHandler(new ScopeTreeReadyEvent.Handler()

src/gwt/src/org/rstudio/studio/client/workbench/views/source/Source.java

@@ -1,7 +1,7 @@
 /*
  * Source.java
  *
- * Copyright (C) 2009-19 by RStudio, Inc.
+ * Copyright (C) 2009-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -65,6 +65,7 @@
 import org.rstudio.studio.client.application.ApplicationAction;
 import org.rstudio.studio.client.application.ApplicationUtils;
 import org.rstudio.studio.client.application.Desktop;
+import org.rstudio.studio.client.application.events.AriaLiveStatusEvent;
 import org.rstudio.studio.client.application.events.CrossWindowEvent;
 import org.rstudio.studio.client.application.events.EventBus;
 import org.rstudio.studio.client.common.FileDialogs;
@@ -4184,6 +4185,19 @@ public void onOpenPreviousFileOnFilesystem()
       openAdjacentFile(false);
    }
 
+   @Handler
+   public void onSpeakEditorLocation()
+   {
+      String announcement;
+      if (view_.getTabCount() == 0)
+         announcement = "No documents open in editor";
+      else
+      {
+         announcement = "Nothing to see here";
+      }
+      events_.fireEvent(new AriaLiveStatusEvent(announcement, true));
+   }
+
    @Handler
    public void onZoomIn()
    {

src/gwt/src/org/rstudio/studio/client/workbench/views/source/SourceShim.java

@@ -1,7 +1,7 @@
 /*
  * SourceShim.java
  *
- * Copyright (C) 2009-19 by RStudio, Inc.
+ * Copyright (C) 2009-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -155,7 +155,9 @@ public abstract static class AsyncSource extends AsyncShim<Source>
       public abstract void onOpenNextFileOnFilesystem();
       @Handler
       public abstract void onOpenPreviousFileOnFilesystem();
-
+      @Handler
+      public abstract void onSpeakEditorLocation();
+
       // NOTE: These aren't really Source-level commands, but we
       // need them to be registered for both the whole application
       // as well as popped-out source windows.

src/gwt/src/org/rstudio/studio/client/workbench/views/source/editors/codebrowser/CodeBrowserEditingTarget.java

@@ -1,7 +1,7 @@
 /*
  * CodeBrowserEditingTarget.java
  *
- * Copyright (C) 2009-19 by RStudio, Inc.
+ * Copyright (C) 2009-20 by RStudio, Inc.
  *
  * Unless you have received this program directly from RStudio pursuant
  * to the terms of a commercial license agreement with RStudio, then
@@ -88,6 +88,7 @@ public interface Display extends TextDisplay,
       void findPrevious();
       void findFromSelection();
       void scrollToLeft();
+      void setAccessibleName(String name);
    }
 
    interface MyBinder extends CommandBinder<Commands, CodeBrowserEditingTarget>
@@ -201,6 +202,9 @@ public void execute()
       {
          docDisplay_.setCode("", false);
       }
+
+      name_.addValueChangeHandler(event -> view_.setAccessibleName(name_.getValue()));
+      name_.fireChangeEvent();
    }
 
    public void showFunction(SearchPathFunctionDefinition functionDef)
@@ -812,8 +816,7 @@ public void onResponseReceived(
    private SourceDocument doc_;
 
    private final Value<Boolean> dirtyState_ = new Value<Boolean>(false);
-   private ArrayList<HandlerRegistration> releaseOnDismiss_ =
-         new ArrayList<HandlerRegistration>();
+   private ArrayList<HandlerRegistration> releaseOnDismiss_ = new ArrayList<>();
    private final SourceServerOperations server_;
    private final Commands commands_;
    private final EventBus events_;
@@ -823,7 +826,7 @@ public void onResponseReceived(
    private Display view_;
    private HandlerRegistration commandReg_;
    private boolean shownWarningBar_ = false;
-   private final Value<String> name_ = new Value<String>("Source Viewer");  
+   private final Value<String> name_ = new Value<>("Source Viewer");
    private DocDisplay docDisplay_;
    private EditingTargetCodeExecution codeExecution_;