Use input method's context for tracking focus states in OnGrabNotify.

chrome/browser/renderer_host/render_widget_host_view_gtk.h

Index: chrome/browser/renderer_host/render_widget_host_view_gtk.h
diff --git a/chrome/browser/renderer_host/render_widget_host_view_gtk.h b/chrome/browser/renderer_host/render_widget_host_view_gtk.h
index af0f17fee323aa6436453a14a8b813c999c73e1e..d93b9a1b37e359d9d32512fdf91d5ec1ab631b74 100644
--- a/chrome/browser/renderer_host/render_widget_host_view_gtk.h
+++ b/chrome/browser/renderer_host/render_widget_host_view_gtk.h
@@ -211,9 +211,10 @@ class RenderWidgetHostViewGtk : public RenderWidgetHostView,
   // We ignore the first mouse release on popups so the popup will remain open.
   bool is_popup_first_mouse_release_;
 
-  // Whether or not this widget was focused before shadowed by another widget.
-  // Used in OnGrabNotify() handler to track the focused state correctly.
-  bool was_focused_before_grab_;
+  // Whether or not this widget's input context was focused before being
+  // shadowed by another widget. Used in OnGrabNotify() handler to track the
+  // focused state correctly.
+  bool was_imcontext_focused_before_grab_;
 
   // True if we are responsible for creating an X grab. This will only be used
   // for <select> dropdowns. It should be true for most such cases, but false