Allow only responsive websites to install as a web app on mobile.

chrome/browser/android/banners/app_banner_data_fetcher_android.h

Index: chrome/browser/android/banners/app_banner_data_fetcher_android.h
diff --git a/chrome/browser/android/banners/app_banner_data_fetcher_android.h b/chrome/browser/android/banners/app_banner_data_fetcher_android.h
index e059522e634851aaf6bd37b46f20af92c478e5cf..0f296dd896ca1d710d3aa9f467f61d880acb5725 100644
--- a/chrome/browser/android/banners/app_banner_data_fetcher_android.h
+++ b/chrome/browser/android/banners/app_banner_data_fetcher_android.h
@@ -26,6 +26,16 @@ class AppBannerDataFetcherAndroid : public AppBannerDataFetcher {
                         base::android::ScopedJavaLocalRef<jobject> app_data,
                         const GURL& image_url);
 
+  using AppBannerDataFetcher::OnMessageReceived;

[benwells, 2015/06/11 01:54:24]

Why do you have this?

[dominickn (DO NOT USE), 2015/06/11 03:32:12]

The parent class OnMessageReceived() has a different signature to the one in
this class. This using statement is needed so that the child class method
doesn't hide the parent class method (even though they take different
arguments). It crashes without this statement.

+
+  // WebContentsObserver override.
+  bool OnMessageReceived(const IPC::Message& message) override;

[benwells, 2015/06/11 01:54:24]

Do these overrides need to be public? Can they be protected or private instead?

[dominickn (DO NOT USE), 2015/06/11 03:32:12]

HandleWebApp should be protected (it's protected in the parent class). Thanks!

[benwells, 2015/06/15 04:14:59]

OnMessageReceived should also be protected or private. Nothing that knows of
this as an AppbannerDataFetcherAndroid should be calling this function, only
bits of the code that know of it as a WebContentsObserver.

+
+  // AppBannerDataFetcher override. Queries the site's meta viewport tag to
+  // detect whether it is responsive, and proceeds by calling the base class
+  // implementation.
+  void HandleWebApp(content::WebContents* web_contents) override;
+
  protected:
   ~AppBannerDataFetcherAndroid() override;
 
@@ -35,6 +45,11 @@ class AppBannerDataFetcherAndroid : public AppBannerDataFetcher {
                   const base::string16& title) override;
 
  private:
+  void OnDidRetrieveMetaTagContent(bool success,
+                                   const std::string& tag_name,
+                                   const std::string& tag_content,
+                                   const GURL& expected_url);
+
   base::android::ScopedJavaGlobalRef<jobject> native_app_data_;
   std::string native_app_package_;