[M90-LTS] Don't call through a protocol handler if they've changed

Have any protocol handler change invalidate the list of protocol
handlers in the context menu.

(cherry picked from commit 2738faa)

Bug: 1227315
Change-Id: Iab8e475454cd946f153102111b02f73de24648fb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3017137
Commit-Queue: Robert Sesek <rsesek@chromium.org>
Auto-Submit: Avi Drissman <avi@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#900104}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3041344
Owners-Override: Jana Grill <janagrill@google.com>
Commit-Queue: Roger Felipe Zanoni da Silva <rzanoni@google.com>
Reviewed-by: Artem Sumaneev <asumaneev@google.com>
Reviewed-by: Victor-Gabriel Savu <vsavu@google.com>
Cr-Commit-Position: refs/branch-heads/4430@{#1543}
Cr-Branched-From: e5ce7dc-refs/heads/master@{#857950}

chrome/browser/renderer_context_menu/render_view_context_menu.cc

@@ -1834,6 +1834,10 @@ void RenderViewContextMenu::AppendProtocolHandlerSubMenu() {
       GetHandlersForLinkUrl();
   if (handlers.empty())
     return;
+
+  protocol_handler_registry_observation_.Observe(protocol_handler_registry_);
+  is_protocol_submenu_valid_ = true;
+
   size_t max = IDC_CONTENT_CONTEXT_PROTOCOL_HANDLER_LAST -
                IDC_CONTENT_CONTEXT_PROTOCOL_HANDLER_FIRST;
   for (size_t i = 0; i < handlers.size() && i <= max; i++) {
@@ -2598,6 +2602,10 @@ RenderViewContextMenu::GetHandlersForLinkUrl() {
   return handlers;
 }
 
+void RenderViewContextMenu::OnProtocolHandlerRegistryChanged() {
+  is_protocol_submenu_valid_ = false;
+}
+
 void RenderViewContextMenu::NotifyMenuShown() {
   auto* cb = GetMenuShownCallback();
   if (!cb->is_null())
@@ -2894,6 +2902,13 @@ void RenderViewContextMenu::ExecOpenWebApp() {
 
 void RenderViewContextMenu::ExecProtocolHandler(int event_flags,
                                                 int handler_index) {
+  if (!is_protocol_submenu_valid_) {
+    // A protocol was changed since the time that the menu was built, so the
+    // index passed in isn't valid. The only thing that can be done now safely
+    // is to bail.
+    return;
+  }
+
   ProtocolHandlerRegistry::ProtocolHandlerList handlers =
       GetHandlersForLinkUrl();
   if (handlers.empty())

chrome/browser/renderer_context_menu/render_view_context_menu.h

@@ -12,7 +12,9 @@
 
 #include "base/files/file_path.h"
 #include "base/observer_list.h"
+#include "base/scoped_observation.h"
 #include "base/strings/string16.h"
+#include "build/build_config.h"
 #include "build/chromeos_buildflags.h"
 #include "chrome/browser/custom_handlers/protocol_handler_registry.h"
 #include "chrome/browser/ui/browser.h"
@@ -68,7 +70,8 @@ namespace ui {
 class DataTransferEndpoint;
 }
 
-class RenderViewContextMenu : public RenderViewContextMenuBase {
+class RenderViewContextMenu : public RenderViewContextMenuBase,
+                              public ProtocolHandlerRegistry::Observer {
  public:
   RenderViewContextMenu(content::RenderFrameHost* render_frame_host,
                         const content::ContextMenuParams& params);
@@ -256,15 +259,29 @@ class RenderViewContextMenu : public RenderViewContextMenuBase {
   // on URL.
   ProtocolHandlerRegistry::ProtocolHandlerList GetHandlersForLinkUrl();
 
+  // ProtocolHandlerRegistry::Observer:
+  void OnProtocolHandlerRegistryChanged() override;
+
   // The destination URL to use if the user tries to search for or navigate to
   // a text selection.
   GURL selection_navigation_url_;
 
   ui::SimpleMenuModel profile_link_submenu_model_;
   std::vector<base::FilePath> profile_link_paths_;
   bool multiple_profiles_open_;
+
+  // Protocol handling:
+  // - The submenu containing the installed protocol handlers.
   ui::SimpleMenuModel protocol_handler_submenu_model_;
+  // - The registry with the protocols.
   ProtocolHandlerRegistry* protocol_handler_registry_;
+  // - The observation of the registry.
+  base::ScopedObservation<ProtocolHandlerRegistry,
+                          ProtocolHandlerRegistry::Observer>
+      protocol_handler_registry_observation_{this};
+  // - Whether or not the registered protocols have changed since the menu was
+  //   built.
+  bool is_protocol_submenu_valid_ = false;
 
   // An observer that handles spelling suggestions, "Add to dictionary", and
   // "Use enhanced spell check" items.