Trigger app banner when add to homescreen is pressed and WebAPKs are enabled.

chrome/browser/android/webapps/add_to_homescreen_manager.cc

Index: chrome/browser/android/webapps/add_to_homescreen_manager.cc
diff --git a/chrome/browser/android/webapps/add_to_homescreen_manager.cc b/chrome/browser/android/webapps/add_to_homescreen_manager.cc
index d7e5929cce20b287d60081bf160abd4bde2a3244..666945efb6fa25ab39cac8e4cccccfd9331a3b49 100644
--- a/chrome/browser/android/webapps/add_to_homescreen_manager.cc
+++ b/chrome/browser/android/webapps/add_to_homescreen_manager.cc
@@ -8,11 +8,15 @@
 #include "base/android/jni_string.h"
 #include "base/guid.h"
 #include "base/location.h"
+#include "base/memory/ptr_util.h"
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
+#include "chrome/browser/android/banners/app_banner_infobar_delegate_android.h"
 #include "chrome/browser/android/shortcut_helper.h"
 #include "chrome/browser/android/webapk/chrome_webapk_host.h"
 #include "chrome/browser/banners/app_banner_settings_helper.h"
+#include "chrome/browser/infobars/infobar_service.h"
+#include "chrome/browser/ui/android/infobars/app_banner_infobar_android.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/origin_util.h"
@@ -129,13 +133,15 @@ void AddToHomescreenManager::RecordAddToHomescreen() {
 
 void AddToHomescreenManager::OnDidDetermineWebApkCompatibility(
     bool is_webapk_compatible) {
-  // TODO(pkotwicz): Select whether to use dialog or not based on
-  // |is_webapk_compatible|.
-  ShowDialog();
+  is_webapk_compatible_ = is_webapk_compatible;
+  if (!is_webapk_compatible)
+    ShowDialog();
 }
 
 void AddToHomescreenManager::OnUserTitleAvailable(
     const base::string16& user_title) {
+  if (is_webapk_compatible_)
+    return;
   JNIEnv* env = base::android::AttachCurrentThread();
   ScopedJavaLocalRef<jstring> j_user_title =
       base::android::ConvertUTF16ToJavaString(env, user_title);
@@ -146,6 +152,11 @@ void AddToHomescreenManager::OnUserTitleAvailable(
 
 void AddToHomescreenManager::OnDataAvailable(const ShortcutInfo& info,
                                              const SkBitmap& icon) {
+  if (is_webapk_compatible_) {
+    CreateInfoBarForWebAPK(info, icon);
+    return;
+  }
+
   JNIEnv* env = base::android::AttachCurrentThread();
   ScopedJavaLocalRef<jobject> java_bitmap;
   if (icon.getSize())
@@ -157,6 +168,37 @@ void AddToHomescreenManager::OnDataAvailable(const ShortcutInfo& info,
     AddShortcut(info, icon);
 }
 
+void AddToHomescreenManager::CreateInfoBarForWebAPK(const ShortcutInfo& info,
+                                                    const SkBitmap& icon) {
+  std::unique_ptr<banners::AppBannerInfoBarDelegateAndroid> delegate_ptr =
+      base::MakeUnique<banners::AppBannerInfoBarDelegateAndroid>(
+          nullptr, info.user_title, base::MakeUnique<ShortcutInfo>(info),
+          base::MakeUnique<SkBitmap>(icon),
+          -1 /* event_request_id */, true /* is_webapk */);
+
+  std::unique_ptr<infobars::InfoBar> infobar_ptr =
+      base::MakeUnique<AppBannerInfoBarAndroid>(
+          std::move(delegate_ptr), data_fetcher_->shortcut_info().url, true);
+  if (!infobar_ptr.get()) {
+    LOG(ERROR) << "Failed to create infobar to install the WebAPK.";
+    return;
+  }
+
+  content::WebContents* web_contents = data_fetcher_->web_contents();
+  if (!web_contents) {
+    LOG(ERROR) << "Failed to create infobar to install the WebAPK: "
+                << "the associated WebContents is null.";
+    return;
+  }
+
+  banners::AppBannerInfoBarDelegateAndroid* delegate =
+      infobar_ptr.get()->delegate()->AsAppBannerInfoBarDelegateAndroid();

[Peter Kasting, 2016/09/06 19:31:23]

Don't add this function.  You don't need it and we want to avoid expanding the
surface in infobar_delegate.h unless necessary.  We should only add such things
when people need to do RTTI-like runtime type checking.

Do something like this instead:

  auto infobar_delegate =
      base::MakeUnique<banners::AppBannerInfoBarDelegateAndroid>(...);
  auto* raw_delegate = infobar_delegate.get();
  content::WebContents* web_contents = data_fetcher_->web_contents();
  if (InfoBarService::FromWebContents(web_contents)->AddInfoBar(
          base::MakeUnique<AppBannerInfoBarAndroid>(
              std::move(infobar_delegate), data_fetcher_->shortcut_info().url,
              true)))
    raw_delegate->InstallWebApk(web_contents);

Several notes on this.

* I used auto more aggressively to reduce typename duplication and verbosity.
* LOG(ERROR) is generally undesirable.  It means "this can fail at runtime" but
doesn't say when/why.  It bloats the executable with the logging strings.  And
people generally don't have a plan on how to collect and analyze the LOG data
anyway.  Usually these should either be removed, replaced by DCHECKs, or
replaced by simple conditional returns/error-handling.
* In the specific cases here, the first LOG() can never fire because memory
allocation would have had to fail (which would have resulted in a forced crash
before returning).  Whether the second can fire is unclear to me; if this can
ever actually be null it should probably be a conditional return, but ensuring
it can't be null and then doing nothing or using a DCHECK to assure the reader
of that would be better.
* You need to check the return value of AddInfoBar().  Don't assume it
succeeded.
* I avoided using "_ptr" to distinguish types because people have different
intuitions on whether it means the "unique_ptr" (because the suffix matches) or
the "raw pointer" (because that's an actual pointer and not an object).  My
instinct is the latter, for example.  "Raw", OTOH, is clear.

[Xi Han, 2016/09/07 15:53:17]

Thanks for all the suggestions. I will be more careful in the future.

+
+  InfoBarService::FromWebContents(web_contents)->AddInfoBar(
+      std::move(infobar_ptr));
+  delegate->InstallWebApk(web_contents);
+}
+
 SkBitmap AddToHomescreenManager::FinalizeLauncherIconInBackground(
     const SkBitmap& bitmap,
     const GURL& url,