Mac: move content::RenderWidgetResizeHelper to ui::WindowResizeHelperMac (acelerated_widget_mac)

We need composited UI on Mac to cooperate with the GPU process in a
similar way to how a Mac RenderWidget does this for composited content.

By separating out the content dependencies from
RenderWidgetResizeHelper, it then becomes a reasonably straightforward
move to src/ui/accelerated_widget_mac.

This allows resize operations performed on views::BridgedNativeWidget to
hook into the same resize task coordination paths as the
RenderWidgetHostView.

One tricky bit: a call to BrowserThread::GetMessageLoopProxyForThread(
BrowserThread::UI)). ui/accelerated_widget_mac can't depend on content,
so it needs to be informed about the UI thread's task runner before any
renderers are created. Doing the initialization in
BrowserMainLoop::PreCreateThreads() ensures the initialization happens
before the IO thread is created.

BUG=531831

Review URL: https://codereview.chromium.org/1354533002

Cr-Commit-Position: refs/heads/master@{#350449}


CrOS-Libchrome-Original-Commit: ef4c91b0545cd2190ef0650d03662e823d1cf6b0
1 file changed
tree: cea3d0d13f544ad64e28bd8e40aa0cea407a8e6a
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/