Restore SnapshotTabHelper temporarily

chrome/renderer/chrome_render_view_observer.cc

 // Copyright (c) 2012 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_view_observer.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 176 matching lines @@
     OnSetClientSidePhishingDetection(true);
 }
 
 ChromeRenderViewObserver::~ChromeRenderViewObserver() {
 }
 
 bool ChromeRenderViewObserver::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(ChromeRenderViewObserver, message)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_WebUIJavaScript, OnWebUIJavaScript)
+    IPC_MESSAGE_HANDLER(ChromeViewMsg_CaptureSnapshot, OnCaptureSnapshot)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_HandleMessageFromExternalHost,
                         OnHandleMessageFromExternalHost)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_JavaScriptStressTestControl,
                         OnJavaScriptStressTestControl)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_SetAllowDisplayingInsecureContent,
                         OnSetAllowDisplayingInsecureContent)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_SetAllowRunningInsecureContent,
                         OnSetAllowRunningInsecureContent)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_SetClientSidePhishingDetection,
                         OnSetClientSidePhishingDetection)
@@ skipping 21 matching lines @@
     const string16& jscript,
     int id,
     bool notify_result) {
   webui_javascript_.reset(new WebUIJavaScript());
   webui_javascript_->frame_xpath = frame_xpath;
   webui_javascript_->jscript = jscript;
   webui_javascript_->id = id;
   webui_javascript_->notify_result = notify_result;
 }
 
+void ChromeRenderViewObserver::OnCaptureSnapshot() {
+  SkBitmap snapshot;
+  bool error = false;
+
+  WebFrame* main_frame = render_view()->GetWebView()->mainFrame();
+  if (!main_frame)
+    error = true;
+
+  if (!error && !CaptureSnapshot(render_view()->GetWebView(), &snapshot))
+    error = true;
+
+  DCHECK(error == snapshot.empty()) <<
+      "Snapshot should be empty on error, non-empty otherwise.";
+
+  // Send the snapshot to the browser process.
+  Send(new ChromeViewHostMsg_Snapshot(routing_id(), snapshot));
+}
+
 void ChromeRenderViewObserver::OnHandleMessageFromExternalHost(
     const std::string& message,
     const std::string& origin,
     const std::string& target) {
   if (message.empty())
     return;
   GetExternalHostBindings()->ForwardMessageFromExternalHost(message, origin,
                                                             target);
 }
 
@@ skipping 521 matching lines @@
   // partial word indexed at the end that might have been clipped. Therefore,
   // terminate the string at the last space to ensure no words are clipped.
   if (contents->size() == kMaxIndexChars) {
     size_t last_space_index = contents->find_last_of(kWhitespaceUTF16);
     if (last_space_index == std::wstring::npos)
       return;  // don't index if we got a huge block of text with no spaces
     contents->resize(last_space_index);
   }
 }
 
+bool ChromeRenderViewObserver::CaptureSnapshot(WebView* view,
+                                               SkBitmap* snapshot) {
+  base::TimeTicks beginning_time = base::TimeTicks::Now();
+
+  view->layout();
+  const WebSize& size = view->size();
+
+  skia::RefPtr<SkCanvas> canvas = skia::AdoptRef(
+      skia::CreatePlatformCanvas(
+          size.width, size.height, true, NULL, skia::RETURN_NULL_ON_FAILURE));
+  if (!canvas)
+    return false;
+
+  view->paint(webkit_glue::ToWebCanvas(canvas.get()),
+              WebRect(0, 0, size.width, size.height));
+  // TODO: Add a way to snapshot the whole page, not just the currently
+  // visible part.
+
+  SkDevice* device = skia::GetTopDevice(*canvas);
+
+  const SkBitmap& bitmap = device->accessBitmap(false);
+  if (!bitmap.copyTo(snapshot, SkBitmap::kARGB_8888_Config))
+    return false;
+
+  UMA_HISTOGRAM_TIMES("Renderer4.Snapshot",
+                  base::TimeTicks::Now() - beginning_time);
+  return true;
+}
+
 ExternalHostBindings* ChromeRenderViewObserver::GetExternalHostBindings() {
   if (!external_host_bindings_.get()) {
     external_host_bindings_.reset(new ExternalHostBindings(
         render_view(), routing_id()));
   }
   return external_host_bindings_.get();
 }
 
 bool ChromeRenderViewObserver::IsStrictSecurityHost(const std::string& host) {
   return (strict_security_hosts_.find(host) != strict_security_hosts_.end());
 }