Dispatch Edit Commands at the focused frame.

In https://chromium-review.googlesource.com/c/chromium/src/+/2243266 I
missed that the edit commands were dispatched at the focused frame
from the root frame widget. This caused a slight issue with Ctrl-left
arrow on gmail causing a history back navigation.

BUG=1099459

Change-Id: Iadb39bd3e031dca6e7c1165bf1be674b5de1f978
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2275490
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Reviewed-by: Mustaq Ahmed <mustaq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#784854}

third_party/blink/renderer/core/frame/web_frame_widget_base.cc

@@ -1120,11 +1120,14 @@ void WebFrameWidgetBase::AddEditCommandForNextKeyEvent(const WebString& name,
 
 bool WebFrameWidgetBase::HandleCurrentKeyboardEvent() {
   bool did_execute_command = false;
+  WebLocalFrame* frame = FocusedWebLocalFrameInWidget();
+  if (!frame)
+    frame = local_root_;
   for (const auto& command : edit_commands_) {
     // In gtk and cocoa, it's possible to bind multiple edit commands to one
     // key (but it's the exception). Once one edit command is not executed, it
     // seems safest to not execute the rest.
-    if (!local_root_->ExecuteCommand(command->name, command->value))
+    if (!frame->ExecuteCommand(command->name, command->value))
       break;
     did_execute_command = true;
   }