Fix the browser not being notified when a webview embedder handles a navigation.

content/renderer/render_frame_impl.cc

Index: content/renderer/render_frame_impl.cc
diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index 5a7b20148ac4011cbe71da2b291f1ec54410e926..b5265b568b18a623dcf83f63ea1c9ea81ece3da7 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -5264,6 +5264,10 @@ WebNavigationPolicy RenderFrameImpl::decidePolicyForNavigation(
           this, is_content_initiated, render_view_was_created_by_renderer,
           frame_, info.urlRequest, info.navigationType, info.defaultPolicy,
           is_redirect)) {
+    if (IsBrowserSideNavigationEnabled()) {
+      // Need to let the browser know so it can notify its observers.
+      Send(new FrameHostMsg_NavigationHandledByEmbedder(routing_id_));

[sgurun-gerrit only, 2017/03/11 02:33:40]

I wonder if there is a better way to do this. We wanted to remove this code as
it is only used for Webview's shouldoverrideurlloading, see
https://cs.chromium.org/chromium/src/android_webview/renderer/aw_content_rend...

[jam, 2017/03/11 05:15:07]

Seems like the question of when it's ok to remove this is orthogonal from this
fix? If you have any better suggestions for how to fix this API with PlzNavigate
though I'm all ears.

+    }
     return blink::WebNavigationPolicyIgnore;
   }
 #endif