Mojoify the RequestThumbnailForContextNode IPC message and reply

chrome/renderer/chrome_render_frame_observer.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/renderer/chrome_render_frame_observer.h"
 
 #include <stddef.h>
 #include <string.h>
 
 #include <limits>
@@ skipping 98 matching lines @@
 }  // namespace
 
 ChromeRenderFrameObserver::ChromeRenderFrameObserver(
     content::RenderFrame* render_frame)
     : content::RenderFrameObserver(render_frame),
       translate_helper_(nullptr),
       phishing_classifier_(nullptr) {
   render_frame->GetInterfaceRegistry()->AddInterface(
       base::Bind(&ChromeRenderFrameObserver::OnImageContextMenuRendererRequest,
                  base::Unretained(this)));
+  render_frame->GetInterfaceRegistry()->AddInterface(
+      base::Bind(&ChromeRenderFrameObserver::OnThumbnailCapturerRequest,
+                 base::Unretained(this)));
 
   // Don't do anything else for subframes.
   if (!render_frame->IsMainFrame())
     return;
 
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
   if (!command_line.HasSwitch(switches::kDisableClientSidePhishingDetection))
     OnSetClientSidePhishingDetection(true);
   translate_helper_ = new translate::TranslateHelper(
@@ skipping 13 matching lines @@
   IPC_END_MESSAGE_MAP()
   if (handled)
     return false;
 
   IPC_BEGIN_MESSAGE_MAP(ChromeRenderFrameObserver, message)
     // TODO(nigeltao): delete the
     // ChromeViewMsg_RequestReloadImageForContextNode handler when
     // tab_android.cc's use is converted to Mojo.
     IPC_MESSAGE_HANDLER(ChromeViewMsg_RequestReloadImageForContextNode,
                         RequestReloadImageForContextNode)
-    IPC_MESSAGE_HANDLER(ChromeViewMsg_RequestThumbnailForContextNode,
-                        OnRequestThumbnailForContextNode)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_SetClientSidePhishingDetection,
                         OnSetClientSidePhishingDetection)
 #if BUILDFLAG(ENABLE_PRINTING)
     IPC_MESSAGE_HANDLER(PrintMsg_PrintNodeUnderContextMenu,
                         OnPrintNodeUnderContextMenu)
 #endif
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
 
   return handled;
@@ skipping 18 matching lines @@
 void ChromeRenderFrameObserver::RequestReloadImageForContextNode() {
   WebLocalFrame* frame = render_frame()->GetWebFrame();
   // TODO(dglazkov): This code is clearly in the wrong place. Need
   // to investigate what it is doing and fix (http://crbug.com/606164).
   WebNode context_node = frame->contextMenuNode();
   if (!context_node.isNull() && context_node.isElementNode()) {
     frame->reloadImage(context_node);
   }
 }
 
-void ChromeRenderFrameObserver::OnRequestThumbnailForContextNode(
-    int thumbnail_min_area_pixels,
+void ChromeRenderFrameObserver::RequestThumbnailForContextNode(
+    int32_t thumbnail_min_area_pixels,
     const gfx::Size& thumbnail_max_size_pixels,
-    int callback_id) {
+    const RequestThumbnailForContextNodeCallback& callback) {
   WebNode context_node = render_frame()->GetWebFrame()->contextMenuNode();
   SkBitmap thumbnail;
   gfx::Size original_size;
   if (!context_node.isNull() && context_node.isElementNode()) {
     blink::WebImage image = context_node.to<WebElement>().imageContents();
     original_size = image.size();
-    thumbnail = Downscale(image,
-                          thumbnail_min_area_pixels,
-                          thumbnail_max_size_pixels);
+    thumbnail =
+        Downscale(image, thumbnail_min_area_pixels, thumbnail_max_size_pixels);
   }
 
   SkBitmap bitmap;
   if (thumbnail.colorType() == kN32_SkColorType)
     bitmap = thumbnail;
   else
     thumbnail.copyTo(&bitmap, kN32_SkColorType);
 
-  std::string thumbnail_data;
+  std::vector<uint8_t> thumbnail_data;
   SkAutoLockPixels lock(bitmap);
   if (bitmap.getPixels()) {
     const int kDefaultQuality = 90;
     std::vector<unsigned char> data;
     if (gfx::JPEGCodec::Encode(
             reinterpret_cast<unsigned char*>(bitmap.getAddr32(0, 0)),
             gfx::JPEGCodec::FORMAT_SkBitmap, bitmap.width(), bitmap.height(),
-            static_cast<int>(bitmap.rowBytes()), kDefaultQuality, &data))
-      thumbnail_data = std::string(data.begin(), data.end());
+            static_cast<int>(bitmap.rowBytes()), kDefaultQuality, &data)) {
+      std::swap(thumbnail_data, data);

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

The standard mechanism for using swap is:

using std::swap;
swap(thumbnail_data, data);

This ensures that you get the efficient swap() overload for the type (if
defined). In this case, it doesn't matter, because std::vector is in namespace
std, but it's probably best to use the standard pattern.

Alternatively, just write:

thumbnail_data.swap(data);

And avoid this entire question =)

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

Ah thanks, I wasn't aware. I just like how the nonmember function looks :P
Fixed.

+    }
   }
 
-  Send(new ChromeViewHostMsg_RequestThumbnailForContextNode_ACK(
-      routing_id(), thumbnail_data, original_size, callback_id));
+  callback.Run(thumbnail_data, original_size);
 }
 
 void ChromeRenderFrameObserver::OnPrintNodeUnderContextMenu() {
 #if BUILDFLAG(ENABLE_PRINTING)
   printing::PrintWebViewHelper* helper =
       printing::PrintWebViewHelper::Get(render_frame());
   if (helper)
     helper->PrintNode(render_frame()->GetWebFrame()->contextMenuNode());
 #endif
 }
@@ skipping 116 matching lines @@
 }
 
 void ChromeRenderFrameObserver::OnDestruct() {
   delete this;
 }
 
 void ChromeRenderFrameObserver::OnImageContextMenuRendererRequest(
     chrome::mojom::ImageContextMenuRendererRequest request) {
   image_context_menu_renderer_bindings_.AddBinding(this, std::move(request));
 }
+
+void ChromeRenderFrameObserver::OnThumbnailCapturerRequest(
+    chrome::mojom::ThumbnailCapturerRequest request) {
+  thumbnail_capturer_bindings_.AddBinding(this, std::move(request));
+}