[Picture-in-Picture] Enable if no GPU compositing.

This reverts https://chromium-review.googlesource.com/1042290 since
cc::Surfaces for video are now allowed to work with software
compositing.

Bug: 806249, 807840
Change-Id: Ie02c69d527b8e13235d744d3c2e98ea5b073f61d
Reviewed-on: https://chromium-review.googlesource.com/1062745Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: François Beaufort <beaufort.francois@gmail.com>
Cr-Commit-Position: refs/heads/master@{#559470}

content/renderer/render_view_impl.cc

@@ -964,14 +964,7 @@ void RenderView::ApplyWebPreferences(const WebPreferences& prefs,
       static_cast<blink::WebEffectiveConnectionType>(
           prefs.low_priority_iframes_threshold));
 
-  // TODO(crbug.com/806249): Remove this once Picture-in-Picture is compatible
-  // without GPU compositing.
-  RenderThreadImpl* render_thread = RenderThreadImpl::current();
-  if (render_thread && render_thread->IsGpuCompositingDisabled()) {
-    settings->SetPictureInPictureEnabled(false);
-  } else {
-    settings->SetPictureInPictureEnabled(prefs.picture_in_picture_enabled);
-  }
+  settings->SetPictureInPictureEnabled(prefs.picture_in_picture_enabled);
 
   settings->SetDataSaverHoldbackWebApi(
       prefs.data_saver_holdback_web_api_enabled);