Refactor Dictation commands to use Macros class.

This matches the abstractions in Android Voice Access, where a macro
is something that can check whether it can execute and can execute,
and is independent from Pumpkin or parsed speech results.

In Dictation, a Macro is an abstract class that should be implemented
for each semantic tag / action. Several high-level macros are created
in this change including a RepeatableKeyPressMacro, used to send
the same key press multiple times via an EventGenerator, and an
InputTextViewMacro, which can put text into a text field via the
chrome.input.ime APIs (in InputController).

No functional changes to Dictation commands should result from this
change.

Checking whether a command can be executed in the given context
is mostly left as a TODO.

TEST=DictationCommandsExtensionTest

AX-Relnotes: N/A
Bug: 1247299,1264544
Change-Id: Ied1add45266b8c5ace0a09a685e86022ae93e9dc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3265812
Reviewed-by: Akihiro Ota <akihiroota@chromium.org>
Commit-Queue: Katie Dektar <katie@chromium.org>
Cr-Commit-Position: refs/heads/main@{#940578}

chrome/browser/resources/chromeos/accessibility/accessibility_common/BUILD.gn

@@ -27,12 +27,17 @@ run_jsbundler("accessibility_common_copied_files") {
     "accessibility_common_loader.js",
     "autoclick/autoclick.js",
     "background.html",
-    "dictation/commands.js",
     "dictation/dictation.js",
     "dictation/earcons/audio_end.wav",
     "dictation/earcons/audio_initiate.wav",
     "dictation/earcons/null_selection.wav",
     "dictation/input_controller.js",
+    "dictation/macros/input_text_view_macro.js",
+    "dictation/macros/list_commands_macro.js",
+    "dictation/macros/macro.js",
+    "dictation/macros/macro_names.js",
+    "dictation/macros/repeatable_key_press_macro.js",
+    "dictation/speech_parser.js",
     "magnifier/magnifier.js",
   ]
   rewrite_rules = [
@@ -155,11 +160,25 @@ js_library("dictation_input_controller") {
   ]
 }
 
-js_library("dictation_commands") {
-  sources = [ "dictation/commands.js" ]
+js_library("dictation_macros") {
+  sources = [
+    "dictation/macros/input_text_view_macro.js",
+    "dictation/macros/list_commands_macro.js",
+    "dictation/macros/macro.js",
+    "dictation/macros/macro_names.js",
+    "dictation/macros/repeatable_key_press_macro.js",
+  ]
   deps = [
+    ":dictation_input_controller",
     "../common:event_generator",
     "../common:key_code",
   ]
-  externs_list = [ "$externs_path/accessibility_private.js" ]
+}
+
+js_library("dictation_commands") {
+  sources = [ "dictation/speech_parser.js" ]
+  deps = [
+    ":dictation_input_controller",
+    ":dictation_macros",
+  ]
 }