Add testRunner.capturePixelsThen() method

This method is similar to displayAsyncThen(), but allows the caller
to get the captured pixel data.

This is to be used in repaint tests to produce the minimum repaint
baselines. This is useful to discover under-repaint bugs with the help
of repaint visualization in layout test results, and to estimate
over-repaints.

R=enne
TBR=dpranke

Review URL: https://codereview.chromium.org/301243022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@277540 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 82 insertions, 3 deletions

diff --git a/content/shell/renderer/test_runner/test_runner.cc b/content/shell/renderer/test_runner/test_runner.cc
index 20fbd0c..667a3f2 100644
--- a/content/shell/renderer/test_runner/test_runner.cc
+++ b/content/shell/renderer/test_runner/test_runner.cc
@@ -20,6 +20,7 @@
 #include "gin/handle.h"
 #include "gin/object_template_builder.h"
 #include "gin/wrappable.h"
+#include "third_party/WebKit/public/platform/WebArrayBuffer.h"
 #include "third_party/WebKit/public/platform/WebBatteryStatus.h"
 #include "third_party/WebKit/public/platform/WebCanvas.h"
 #include "third_party/WebKit/public/platform/WebData.h"
@@ -27,6 +28,7 @@
 #include "third_party/WebKit/public/platform/WebDeviceOrientationData.h"
 #include "third_party/WebKit/public/platform/WebPoint.h"
 #include "third_party/WebKit/public/platform/WebURLResponse.h"
+#include "third_party/WebKit/public/web/WebArrayBufferConverter.h"
 #include "third_party/WebKit/public/web/WebBindings.h"
 #include "third_party/WebKit/public/web/WebDataSource.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
@@ -42,6 +44,7 @@
 #include "third_party/WebKit/public/web/WebSettings.h"
 #include "third_party/WebKit/public/web/WebSurroundingText.h"
 #include "third_party/WebKit/public/web/WebView.h"
+#include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 
 #if defined(__linux__) || defined(ANDROID)
@@ -81,7 +84,8 @@ class InvokeCallbackTask : public WebMethodTask<TestRunner> {
  public:
   InvokeCallbackTask(TestRunner* object, v8::Handle<v8::Function> callback)
       : WebMethodTask<TestRunner>(object),
-        callback_(blink::mainThreadIsolate(), callback) {}
+        callback_(blink::mainThreadIsolate(), callback),
+        argc_(0) {}
 
   virtual void runIfValid() OVERRIDE {
     v8::Isolate* isolate = blink::mainThreadIsolate();
@@ -94,15 +98,32 @@ class InvokeCallbackTask : public WebMethodTask<TestRunner> {
 
     v8::Context::Scope context_scope(context);
 
+    scoped_ptr<v8::Handle<v8::Value>[]> local_argv;
+    if (argc_) {
+        local_argv.reset(new v8::Handle<v8::Value>[argc_]);
+        for (int i = 0; i < argc_; ++i)
+          local_argv[i] = v8::Local<v8::Value>::New(isolate, argv_[i]);
+    }
+
     frame->callFunctionEvenIfScriptDisabled(
         v8::Local<v8::Function>::New(isolate, callback_),
         context->Global(),
-        0,
-        NULL);
+        argc_,
+        local_argv.get());
+  }
+
+  void SetArguments(int argc, v8::Handle<v8::Value> argv[]) {
+    v8::Isolate* isolate = blink::mainThreadIsolate();
+    argc_ = argc;
+    argv_.reset(new v8::UniquePersistent<v8::Value>[argc]);
+    for (int i = 0; i < argc; ++i)
+      argv_[i] = v8::UniquePersistent<v8::Value>(isolate, argv[i]);
   }
 
  private:
   v8::UniquePersistent<v8::Function> callback_;
+  int argc_;
+  scoped_ptr<v8::UniquePersistent<v8::Value>[]> argv_;
 };
 
 class TestRunnerBindings : public gin::Wrappable<TestRunnerBindings> {
@@ -256,6 +277,7 @@ class TestRunnerBindings : public gin::Wrappable<TestRunnerBindings> {
   void RemoveWebPageOverlay();
   void DisplayAsync();
   void DisplayAsyncThen(v8::Handle<v8::Function> callback);
+  void CapturePixelsAsyncThen(v8::Handle<v8::Function> callback);
   void SetCustomTextOutput(std::string output);
   void SetViewSourceForFrame(const std::string& name, bool enabled);
   void setMockPushClientSuccess(const std::string& end_point,
@@ -500,6 +522,7 @@ gin::ObjectTemplateBuilder TestRunnerBindings::GetObjectTemplateBuilder(
                  &TestRunnerBindings::RemoveWebPageOverlay)
       .SetMethod("displayAsync", &TestRunnerBindings::DisplayAsync)
       .SetMethod("displayAsyncThen", &TestRunnerBindings::DisplayAsyncThen)
+      .SetMethod("capturePixelsAsyncThen", &TestRunnerBindings::CapturePixelsAsyncThen)
       .SetMethod("setCustomTextOutput",
                  &TestRunnerBindings::SetCustomTextOutput)
       .SetMethod("setViewSourceForFrame",
@@ -1300,6 +1323,12 @@ void TestRunnerBindings::DisplayAsyncThen(v8::Handle<v8::Function> callback) {
     runner_->DisplayAsyncThen(callback);
 }
 
+void TestRunnerBindings::CapturePixelsAsyncThen(
+    v8::Handle<v8::Function> callback) {
+  if (runner_)
+    runner_->CapturePixelsAsyncThen(callback);
+}
+
 void TestRunnerBindings::SetCustomTextOutput(std::string output) {
   runner_->setCustomTextOutput(output);
 }
@@ -2717,6 +2746,46 @@ void TestRunner::DisplayAsyncThen(v8::Handle<v8::Function> callback) {
                                       base::Passed(&task)));
 }
 
+void TestRunner::CapturePixelsAsyncThen(v8::Handle<v8::Function> callback) {
+  scoped_ptr<InvokeCallbackTask> task(
+      new InvokeCallbackTask(this, callback));
+  proxy_->CapturePixelsAsync(base::Bind(&TestRunner::CapturePixelsCallback,
+                                        base::Unretained(this),
+                                        base::Passed(&task)));
+}
+
+void TestRunner::CapturePixelsCallback(scoped_ptr<InvokeCallbackTask> task,
+                                       const SkBitmap& snapshot) {
+  v8::Isolate* isolate = blink::mainThreadIsolate();
+  v8::HandleScope handle_scope(isolate);
+
+  v8::Handle<v8::Context> context =
+      web_view_->mainFrame()->mainWorldScriptContext();
+  if (context.IsEmpty())
+    return;
+
+  v8::Context::Scope context_scope(context);
+  v8::Handle<v8::Value> argv[3];
+  SkAutoLockPixels snapshot_lock(snapshot);
+
+  int width = snapshot.info().fWidth;
+  DCHECK_NE(0, width);
+  argv[0] = v8::Number::New(isolate, width);
+
+  int height = snapshot.info().fHeight;
+  DCHECK_NE(0, height);
+  argv[1] = v8::Number::New(isolate, height);
+
+  blink::WebArrayBuffer buffer =
+      blink::WebArrayBuffer::create(snapshot.getSize(), 1);
+  memcpy(buffer.data(), snapshot.getPixels(), buffer.byteLength());
+  argv[2] = blink::WebArrayBufferConverter::toV8Value(
+      &buffer, context->Global(), isolate);
+
+  task->SetArguments(3, argv);
+  InvokeCallback(task.Pass());
+}
+
 void TestRunner::SetMockPushClientSuccess(
   const std::string& end_point, const std::string& registration_id) {
   proxy_->GetPushClientMock()->SetMockSuccessValues(end_point, registration_id);
diff --git a/content/shell/renderer/test_runner/test_runner.h b/content/shell/renderer/test_runner/test_runner.h
index 2bda72d..2a1d751 100644
--- a/content/shell/renderer/test_runner/test_runner.h
+++ b/content/shell/renderer/test_runner/test_runner.h
@@ -15,6 +15,8 @@
 #include "content/shell/renderer/test_runner/web_test_runner.h"
 #include "v8/include/v8.h"
 
+class SkBitmap;
+
 namespace blink {
 class WebFrame;
 class WebNotificationPresenter;
@@ -531,12 +533,20 @@ class TestRunner : public WebTestRunner,
   void DisplayAsync();
   void DisplayAsyncThen(v8::Handle<v8::Function> callback);
 
+  // Similar to DisplayAsyncThen(), but pass parameters of the captured
+  // snapshot (width, height, snapshot) to the callback.
+  void CapturePixelsAsyncThen(v8::Handle<v8::Function> callback);
+
   void SetMockPushClientSuccess(const std::string& end_point,
                                 const std::string& registration_id);
   void SetMockPushClientError(const std::string& message);
 
   ///////////////////////////////////////////////////////////////////////////
   // Internal helpers
+
+  void CapturePixelsCallback(scoped_ptr<InvokeCallbackTask> task,
+                             const SkBitmap& snapshot);
+
   void CheckResponseMimeType();
   void CompleteNotifyDone();