[Aura] RenderWidgetHostViewAura fixes for embedding fullscreen views within browser tabs.

1. Modify OnBoundsChanged() to unconditionally call SetSize() to propagate all aura::Window size changes (e.g., due to container layout) to the renderer.  There are already re-entrancy and redundancy guards in place, making this safe/sane.

2. Apply coordinate conversion for mouse events propagated to the parent->delegate.  This was previously overlooked because it was assumed WebContentsViewAura was the only parent->delegate, and WCVA does not do anything with mouse coordinates.

BUG=256870

Review URL: https://codereview.chromium.org/148613008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247628 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 247628
Make generated hosted app icons have white background.

This CL changes the transparent background of icons generated by the "Create app
from this website" button into solid white.

BUG=315632

Review URL: https://codereview.chromium.org/148723003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247629 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 247629