GitLab

Instead expand the Display's size to cover the entire entire external
viewport (aka the clip area).

Also removes SetSurfaceSize from the SoftwareOutputSurface used by
WebView to draw the renderer's frame into an SkCanvas. Since the
Display is now sized to cover the whole clip area, it will Reshape()
to that size and the OutputSurface can use that size.

R=boliu@chromium.org
BUG=606056
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel

Review-Url: https://codereview.chromium.org/2377533002
Cr-Commit-Position: refs/heads/master@{#422960}