Use heuristic to work out when to prompt for app install banners.

chrome/browser/android/banners/app_banner_manager.cc

Index: chrome/browser/android/banners/app_banner_manager.cc
diff --git a/chrome/browser/android/banners/app_banner_manager.cc b/chrome/browser/android/banners/app_banner_manager.cc
index c08e3e963cc37ed6a4df2d70422b24b3b71ec00a..799271a73089f305a5a1be122a16183c5c906111 100644
--- a/chrome/browser/android/banners/app_banner_manager.cc
+++ b/chrome/browser/android/banners/app_banner_manager.cc
@@ -68,16 +68,18 @@ void AppBannerManager::BlockBanner(JNIEnv* env,
 
   GURL url(ConvertJavaStringToUTF8(env, jurl));
   std::string package_name = ConvertJavaStringToUTF8(env, jpackage);
-  AppBannerSettingsHelper::Block(web_contents(), url, package_name);
+  AppBannerSettingsHelper::RecordBannerEvent(
+      web_contents(), url, package_name,
+      AppBannerSettingsHelper::APP_BANNER_EVENT_DID_BLOCK, base::Time::Now());
 }
 
 void AppBannerManager::Block() const {
   if (!web_contents() || manifest_.IsEmpty())
     return;
 
-  AppBannerSettingsHelper::Block(web_contents(),
-                                 web_contents()->GetURL(),
-                                 manifest_.start_url.spec());
+  AppBannerSettingsHelper::RecordBannerEvent(
+      web_contents(), web_contents()->GetURL(), manifest_.start_url.spec(),
+      AppBannerSettingsHelper::APP_BANNER_EVENT_DID_BLOCK, base::Time::Now());
 }
 
 void AppBannerManager::Install() const {
@@ -85,6 +87,11 @@ void AppBannerManager::Install() const {
     return;
 
   if (!manifest_.IsEmpty()) {
+    AppBannerSettingsHelper::RecordBannerEvent(
+        web_contents(), web_contents()->GetURL(), manifest_.start_url.spec(),
+        AppBannerSettingsHelper::APP_BANNER_EVENT_DID_ADD_TO_HOMESCREEN,
+        base::Time::Now());
+
     InstallManifestApp(manifest_, *app_icon_.get());
   }
 }
@@ -171,10 +178,30 @@ void AppBannerManager::OnDidCheckHasServiceWorker(bool has_same) {
     if (icon_url.is_empty())
       return;
 
+    if (!CheckIfShouldShow(manifest_.start_url.spec()))
+      return;
+
     FetchIcon(icon_url);
   }
 }
 
+bool AppBannerManager::CheckIfShouldShow(
+    const std::string& package_or_start_url) {
+  AppBannerSettingsHelper::RecordBannerEvent(
+      web_contents(), validated_url_, package_or_start_url,
+      AppBannerSettingsHelper::APP_BANNER_EVENT_COULD_SHOW, base::Time::Now());
+  if (!AppBannerSettingsHelper::ShouldShowBanner(web_contents(), validated_url_,
+                                                 package_or_start_url,
+                                                 base::Time::Now())) {
+    return false;
+  }
+
+  AppBannerSettingsHelper::RecordBannerEvent(
+      web_contents(), validated_url_, package_or_start_url,
+      AppBannerSettingsHelper::APP_BANNER_EVENT_DID_SHOW, base::Time::Now());

[gone, 2015/02/05 22:21:10]

Seems strange to record that we did show it in a function called
CheckIfShouldShow().  ShowIfPossible()?

[benwells, 2015/02/06 16:36:28]

Good point. I've split this into two functions: RecordCouldShowBanner and
CheckIfShouldShow.

+  return true;
+}
+
 bool AppBannerManager::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(AppBannerManager, message)
@@ -235,11 +262,8 @@ void AppBannerManager::OnDidRetrieveMetaTagContent(
 
   banners::TrackDisplayEvent(DISPLAY_BANNER_REQUESTED);
 
-  if (!AppBannerSettingsHelper::IsAllowed(web_contents(),
-                                          expected_url,
-                                          tag_content)) {
+  if (!CheckIfShouldShow(tag_content))
     return;
-  }
 
   // Send the info to the Java side to get info about the app.
   JNIEnv* env = base::android::AttachCurrentThread();