mac: Make services menu work after hitting "select all"

The problem was that "select all" didn't go through
RenderViewHostImpl::SelectAll(). That method has the effect of setting
handling_select_range_ in RenderViewImpl::OnSelectAll(). Previously, this
bool wasn't set, causing RenderViewImpl::didChangeSelection() to return early,
which in turn meant that the browser process wasn't informed about the updated
selection.

BUG=114870
TEST=Focus a text box, enter some text, hit cmd-a. Check that text services
are selectable in the services menu.

Review URL: https://codereview.chromium.org/12398005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@185904 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/render_widget_host_view_mac.mm

@@ -3351,6 +3351,20 @@ - (void)pasteAndMatchStyle:(id)sender {
   }
 }
 
+- (void)selectAll:(id)sender {
+  // editCommand_helper_ adds implementations for most NSResponder methods
+  // dynamically. But the renderer side only sends selection results back to
+  // the browser if they were triggered by a keyboard event or went through
+  // one of the Select methods on RWH. Since selectAll: is called from the
+  // menu handler, neither is true.
+  // Explicitly call SelectAll() here to make sure the renderer returns
+  // selection results.
+  if (renderWidgetHostView_->render_widget_host_->IsRenderView()) {
+    static_cast<RenderViewHostImpl*>(
+        renderWidgetHostView_->render_widget_host_)->SelectAll();
+  }
+}
+
 - (void)startSpeaking:(id)sender {
   renderWidgetHostView_->SpeakSelection();
 }