Convert app banners to use Mojo.

content/public/renderer/content_renderer_client.h

Index: content/public/renderer/content_renderer_client.h
diff --git a/content/public/renderer/content_renderer_client.h b/content/public/renderer/content_renderer_client.h
index 63e654273416713f055af89a1d30269ef6b0516f..b347604e571556d4c72af7e2291f72e356110201 100644
--- a/content/public/renderer/content_renderer_client.h
+++ b/content/public/renderer/content_renderer_client.h
@@ -32,7 +32,6 @@ class SingleThreadTaskRunner;
 }
 
 namespace blink {
-class WebAppBannerClient;
 class WebAudioDevice;
 class WebClipboard;
 class WebFrame;
@@ -329,10 +328,6 @@ class CONTENT_EXPORT ContentRendererClient {
   // metric. See: https://www.chromium.org/developers/design-documents/rappor
   virtual void RecordRapporURL(const std::string& metric, const GURL& url) {}
 
-  // Allows an embedder to provide a blink::WebAppBannerClient.
-  virtual std::unique_ptr<blink::WebAppBannerClient> CreateAppBannerClient(
-      RenderFrame* render_frame);
-
   // Gives the embedder a chance to add properties to the context menu.
   // Currently only called when the context menu is for an image.
   virtual void AddImageContextMenuProperties(