Fix recursive calls to PaintNow under gtk2.18.3 and up.  gdk_window_process_updates in gtk2.18.3 issues exposure events on its child gdkwindow (with update_children=true) and drives event loop. In current  implementation, WidgetGtk::DidProcessEvent calls PaintNow no matter where  the event was generated to, which causes recursive calls to PaintNow. This cl fix this issue by calling PaintNow only  when the event was for the target WidgetGtk.
Fix recursive calls to PaintNow under gtk2.18.3 and up.
 gdk_window_process_updates in gtk2.18.3 issues exposure events on its child gdkwindow (with update_children=true) and drives event loop. In current  implementation, WidgetGtk::DidProcessEvent calls PaintNow no matter where  the event was generated to, which causes recursive calls to PaintNow. This cl fix this issue by calling PaintNow only  when the event was for the target WidgetGtk.

BUG=42235
TEST=none

Review URL: http://codereview.chromium.org/1741004

git-svn-id: http://src.chromium.org/svn/trunk/src@45461 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: ba78f037a8f6e9354d24e351d47a0334a3cd3dba
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser