Workaround issue of getting 0,0,0,0 inval rects

 Bug: 6142700
 WebKit is sending an empty inval rect for some reason, which results
 in WebView not being invalidated. Assume an empty inval means a
 full inval

Change-Id: Ib93b806f8f8fd2039e2a0e43de2372c3e6be2433
1 file changed