Use a resource throttle to implement shouldOverrideUrlLoading.

android_webview/renderer/aw_content_renderer_client.h

Index: android_webview/renderer/aw_content_renderer_client.h
diff --git a/android_webview/renderer/aw_content_renderer_client.h b/android_webview/renderer/aw_content_renderer_client.h
index c16b506080c35803c3117a3538086b9e4235650b..ab0c7500362c25b4ccc628e6a323f63b402607be 100644
--- a/android_webview/renderer/aw_content_renderer_client.h
+++ b/android_webview/renderer/aw_content_renderer_client.h
@@ -37,14 +37,6 @@ class AwContentRendererClient : public content::ContentRendererClient {
   bool IsLinkVisited(unsigned long long link_hash) override;
   void AddKeySystems(std::vector<media::KeySystemInfo>* key_systems) override;
 
-  bool HandleNavigation(content::RenderFrame* render_frame,
-                        content::DocumentState* document_state,
-                        int opener_id,
-                        blink::WebFrame* frame,
-                        const blink::WebURLRequest& request,
-                        blink::WebNavigationType type,
-                        blink::WebNavigationPolicy default_policy,
-                        bool is_redirect) override;
   bool ShouldOverridePageVisibilityState(
       const content::RenderFrame* render_frame,
       blink::WebPageVisibilityState* override_state) override;