Move didUpdateTopControls call from WebViewImpl::resize to layoutUpdated.

This call was put there recently in case we received a change to the top
controls before the WebView had a size. Unfortunately, the FrameView doesn't
get resized until after layout, meaning when didUpdateTopControls gets
called, the PinchViewport has been resized but the FrameView hasn't. This
led to an incorrect maximumScrollPosition being calculated since the
FrameView adjustment assumes the two viewports have the same aspect ratio.

BUG=428193

Review URL: https://codereview.chromium.org/688083002

git-svn-id: svn://svn.chromium.org/blink/trunk@184608 bbb929c8-8fbe-4397-9dbb-9b2b20218538