Mojoify the RequestThumbnailForContextNode IPC message and reply

chrome/browser/ui/android/context_menu_helper.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/android/context_menu_helper.h"
 
 #include <stdint.h>
 
+#include <vector>
+
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
+#include "base/bind_helpers.h"
 #include "chrome/browser/android/download/download_controller_base.h"
 #include "chrome/browser/ui/tab_contents/core_tab_helper.h"
+#include "chrome/common/thumbnail_capturer.mojom.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_headers.h"
 #include "content/public/browser/android/content_view_core.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/common/context_menu_params.h"
 #include "jni/ContextMenuHelper_jni.h"
 #include "jni/ContextMenuParams_jni.h"
+#include "services/service_manager/public/cpp/interface_provider.h"
 #include "third_party/WebKit/public/web/WebContextMenuData.h"
 #include "ui/android/window_android.h"
 #include "ui/gfx/geometry/point.h"
 
 using base::android::ConvertJavaStringToUTF8;
 using base::android::ConvertUTF8ToJavaString;
 using base::android::ConvertUTF16ToJavaString;
 using base::android::JavaParamRef;
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(ContextMenuHelper);
 
 const int kShareImageMaxWidth = 2048;
 const int kShareImageMaxHeight = 2048;
 
 const char kDataReductionProxyPassthroughHeader[] =
     "Chrome-Proxy: pass-through\r\n";
 
 ContextMenuHelper::ContextMenuHelper(content::WebContents* web_contents)
-    : web_contents_(web_contents) {
+    : web_contents_(web_contents), weak_factory_(this) {
   JNIEnv* env = base::android::AttachCurrentThread();
   java_obj_.Reset(
       env,
       Java_ContextMenuHelper_create(env, reinterpret_cast<long>(this)).obj());
   DCHECK(!java_obj_.is_null());
 }
 
 ContextMenuHelper::~ContextMenuHelper() {
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_ContextMenuHelper_destroy(env, java_obj_);
@@ skipping 92 matching lines @@
       render_frame_host, context_menu_params_.src_url);
 }
 
 void ContextMenuHelper::ShareImage(JNIEnv* env,
                                    const JavaParamRef<jobject>& obj) {
   content::RenderFrameHost* render_frame_host =
       content::RenderFrameHost::FromID(render_process_id_, render_frame_id_);
   if (!render_frame_host)
     return;
 
-  CoreTabHelper::FromWebContents(web_contents_)->
-      RequestThumbnailForContextNode(
-          render_frame_host,
-          0,
-          gfx::Size(kShareImageMaxWidth, kShareImageMaxHeight),
-          base::Bind(&ContextMenuHelper::OnShareImage,
-                     base::Unretained(this)));
+  chrome::mojom::ThumbnailCapturerPtr thumbnail_capturer;
+  render_frame_host->GetRemoteInterfaces()->GetInterface(&thumbnail_capturer);
+  // Bind the InterfacePtr into the callback so that it's kept alive until
+  // there's either a connection error or a response.

[dcheng, 2017/03/13 07:49:29]

Hmm... how come we need to write this? Similar code doesn't seem to:
https://cs.chromium.org/chromium/src/chrome/browser/renderer_context_menu/ren...

[watk, 2017/03/13 23:34:04]

The one you linked to doesn't have a reply callback. So it's fine to delete it
as soon as you make the call because AFAIK the lifetime of the outgoing message
isn't tied to the InterfacePtr. 

In this case we have a reply callback, which will not run after the InterfacePtr
is deleted, so we need to keep it alive until the callback has run (or there's a
connection error). Moving it into the callback is clean because it saves us from
having to maintain any state (a collection of InterfacePtrs with pending
replies). 

+  auto* thumbnail_capturer_proxy = thumbnail_capturer.get();
+  thumbnail_capturer_proxy->RequestThumbnailForContextNode(
+      0, gfx::Size(kShareImageMaxWidth, kShareImageMaxHeight),
+      base::Bind(&ContextMenuHelper::OnShareImage, weak_factory_.GetWeakPtr(),
+                 base::Passed(&thumbnail_capturer)));
 }
 
-void ContextMenuHelper::OnShareImage(const std::string& thumbnail_data,
-                                     const gfx::Size& original_size) {
+void ContextMenuHelper::OnShareImage(
+    chrome::mojom::ThumbnailCapturerPtr thumbnail_capturer,
+    const std::vector<uint8_t>& thumbnail_data,
+    const gfx::Size& original_size) {
   content::ContentViewCore* content_view_core =
       content::ContentViewCore::FromWebContents(web_contents_);
   if (!content_view_core)
     return;
 
   base::android::ScopedJavaLocalRef<jobject> jwindow_android(
       content_view_core->GetWindowAndroid()->GetJavaObject());
 
   if (jwindow_android.is_null())
     return;
 
   JNIEnv* env = base::android::AttachCurrentThread();
   base::android::ScopedJavaLocalRef<jbyteArray> j_bytes =
-      base::android::ToJavaByteArray(
-          env, reinterpret_cast<const uint8_t*>(thumbnail_data.data()),
-          thumbnail_data.length());
+      base::android::ToJavaByteArray(env, thumbnail_data);
 
   Java_ContextMenuHelper_onShareImageReceived(env, java_obj_, jwindow_android,
                                               j_bytes);
 }
 
 bool RegisterContextMenuHelper(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }