<webview>: resizing with display:none set should resize on attachment

BUG=330264, 419020
TEST=WebViewTest.Shim_TestResizeWebviewWithDisplayNoneResizesContent
TBR=creis@chromium.org for minor browser_plugin_delegate.h change.

Review URL: https://codereview.chromium.org/624063002

Cr-Commit-Position: refs/heads/master@{#298133}
8 files changed