Log messages regarding why app banners aren't displayed to the console

chrome/browser/android/banners/app_banner_manager_android.cc

Index: chrome/browser/android/banners/app_banner_manager_android.cc
diff --git a/chrome/browser/android/banners/app_banner_manager_android.cc b/chrome/browser/android/banners/app_banner_manager_android.cc
index 829b0b019296829cc6feabd9b4eaf49d56749ae7..780752f310e6207c2591e6ef338f1a5f43211b02 100644
--- a/chrome/browser/android/banners/app_banner_manager_android.cc
+++ b/chrome/browser/android/banners/app_banner_manager_android.cc
@@ -51,7 +51,7 @@ void AppBannerManagerAndroid::ReplaceWebContents(JNIEnv* env,
 bool AppBannerManagerAndroid::HandleNonWebApp(const std::string& platform,
                                               const GURL& url,
                                               const std::string& id) {
-  if (platform != kPlayPlatform || id.empty())
+  if (!CheckPlatformAndId(platform, id))
     return false;
 
   banners::TrackDisplayEvent(DISPLAY_EVENT_BANNER_REQUESTED);
@@ -71,6 +71,35 @@ bool AppBannerManagerAndroid::HandleNonWebApp(const std::string& platform,
   return true;
 }
 
+bool AppBannerManagerAndroid::CheckPlatformAndId(const std::string& platform,

[benwells, 2015/05/11 08:08:39]

Actually ... this probably shouldn't generate a 'not shown' message, as it might
be shown for the web platform (or not, if there are other problems).

Maybe it should just generate a message saying 'XXX platform application ignored
as not supported on Android' or 'play application ignored as there is no id'.

[dominickn (DO NOT USE), 2015/05/12 07:41:30]

Done.

+                                                 const std::string& id) {
+  if (platform != kPlayPlatform) {
+    banners::SendDebugMessage(web_contents(),
+                              "not shown: application not from Play platform");
+    return false;
+  } else if (id.empty()) {

[benwells, 2015/05/11 08:08:39]

Nit: no else after return (and ditto later).

+    banners::SendDebugMessage(web_contents(),
+                              "not shown: application id is empty");
+    return false;
+  }
+  return true;
+}
+
+bool AppBannerManagerAndroid::CheckFetcherMatchesContents() {
+  if (!data_fetcher()) {
+    banners::SendDebugMessage(web_contents(),
+                              "not shown: data fetcher is not active");

[benwells, 2015/05/11 08:08:39]

This error should be the same as the 'the user navigated' one.

[dominickn (DO NOT USE), 2015/05/12 07:41:30]

Done.

+    return false;
+  } else if (!web_contents()) {
+    return false;
+  } else if (data_fetcher()->validated_url() != web_contents()->GetURL()) {
+    banners::SendDebugMessage(web_contents(),
+                              "not shown: page URL does not match fetcher URL");

[benwells, 2015/05/11 08:08:39]

Same, here, I think this only happens when the user navigates.

[dominickn (DO NOT USE), 2015/05/12 07:41:30]

Done.

+    return false;
+  }
+  return true;
+}
+
 AppBannerDataFetcher* AppBannerManagerAndroid::CreateAppBannerDataFetcher(
     base::WeakPtr<Delegate> weak_delegate,
     const int ideal_icon_size) {
@@ -84,10 +113,8 @@ bool AppBannerManagerAndroid::OnAppDetailsRetrieved(JNIEnv* env,
                                                     jstring japp_title,
                                                     jstring japp_package,
                                                     jstring jicon_url) {
-  if (!data_fetcher() || !web_contents()
-      || data_fetcher()->validated_url() != web_contents()->GetURL()) {
+  if (!CheckFetcherMatchesContents())
     return false;
-  }
 
   base::android::ScopedJavaLocalRef<jobject> native_app_data;
   native_app_data.Reset(env, japp_data);