Linux: For mouse button clicks, only send buttons 1, 2, 3 to the renderer.

BUG=16236
TEST=no more sad tab on clicking mouse back button

Review URL: http://codereview.chromium.org/155250

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@20217 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/renderer_host/render_widget_host_view_gtk.cc

@@ -220,6 +220,9 @@ class RenderWidgetHostViewGtkWidget {
   static gboolean ButtonPressReleaseEvent(
       GtkWidget* widget, GdkEventButton* event,
       RenderWidgetHostViewGtk* host_view) {
+    if (!(event->button == 1 || event->button == 2 || event->button == 3))
+      return FALSE;  // We do not forward any other buttons to the renderer.
+
     // We want to translate the coordinates of events that do not originate
     // from this widget to be relative to the top left of the widget.
     GtkWidget* event_widget = gtk_get_event_widget(
@@ -253,7 +256,7 @@ class RenderWidgetHostViewGtkWidget {
     if (event->type == GDK_BUTTON_PRESS && !GTK_WIDGET_HAS_FOCUS(widget))
       gtk_widget_grab_focus(widget);
 
-    return FALSE;
+    return TRUE;  // We did handle the mouse event.
   }
 
   static gboolean MouseMoveEvent(GtkWidget* widget, GdkEventMotion* event,