Add CreateWithDisableAero, to allow Windows capturer to be created without disabling Aero.

media/video/capture/screen/screen_capturer_win.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 "media/video/capture/screen/screen_capturer.h"
 
 #include <windows.h>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 57 matching lines @@
   ScreenCapturer::Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenCaptureFrameWin);
 };
 
 // ScreenCapturerWin captures 32bit RGB using GDI.
 //
 // ScreenCapturerWin is double-buffered as required by ScreenCapturer.
 class ScreenCapturerWin : public ScreenCapturer {
  public:
-  ScreenCapturerWin();
+  ScreenCapturerWin(bool disable_aero);
   virtual ~ScreenCapturerWin();
 
   // Overridden from ScreenCapturer:
   virtual void Start(Delegate* delegate) OVERRIDE;
   virtual void Stop() OVERRIDE;
   virtual void InvalidateRegion(const SkRegion& invalid_region) OVERRIDE;
   virtual void CaptureFrame() OVERRIDE;
 
  private:
   // Make sure that the device contexts match the screen configuration.
@@ skipping 107 matching lines @@
   CHECK(bitmap_ != NULL);
   CHECK(data != NULL);
 
   set_pixels(reinterpret_cast<uint8*>(data));
   set_dimensions(SkISize::Make(bmi.bmiHeader.biWidth,
                                std::abs(bmi.bmiHeader.biHeight)));
   set_bytes_per_row(
       bmi.bmiHeader.biSizeImage / std::abs(bmi.bmiHeader.biHeight));
 }
 
-ScreenCapturerWin::ScreenCapturerWin()
+ScreenCapturerWin::ScreenCapturerWin(bool disable_aero)
     : delegate_(NULL),
       desktop_dc_rect_(SkIRect::MakeEmpty()),
       composition_func_(NULL),
       set_thread_execution_state_failed_(false) {
+  if (disable_aero) {
+    // Load dwmapi.dll dynamically since it is not available on XP.
+    if (!dwmapi_library_.is_valid()) {
+      base::FilePath path(base::GetNativeLibraryName(
+          UTF8ToUTF16(kDwmapiLibraryName)));
+      dwmapi_library_.Reset(base::LoadNativeLibrary(path, NULL));
+    }
+
+    if (dwmapi_library_.is_valid() && composition_func_ == NULL) {
+      composition_func_ = static_cast<DwmEnableCompositionFunc>(
+          dwmapi_library_.GetFunctionPointer("DwmEnableComposition"));
+    }
+  }
 }
 
 ScreenCapturerWin::~ScreenCapturerWin() {
 }
 
 void ScreenCapturerWin::InvalidateRegion(const SkRegion& invalid_region) {
   helper_.InvalidateRegion(invalid_region);
 }
 
 void ScreenCapturerWin::CaptureFrame() {
@@ skipping 47 matching lines @@
 
   // Check for cursor shape update.
   CaptureCursor();
 }
 
 void ScreenCapturerWin::Start(Delegate* delegate) {
   DCHECK(delegate_ == NULL);
 
   delegate_ = delegate;
 
-  // Load dwmapi.dll dynamically since it is not available on XP.
-  if (!dwmapi_library_.is_valid()) {
-    base::FilePath path(base::GetNativeLibraryName(
-        UTF8ToUTF16(kDwmapiLibraryName)));
-    dwmapi_library_.Reset(base::LoadNativeLibrary(path, NULL));
-  }
-
-  if (dwmapi_library_.is_valid() && composition_func_ == NULL) {
-    composition_func_ = static_cast<DwmEnableCompositionFunc>(
-        dwmapi_library_.GetFunctionPointer("DwmEnableComposition"));
-  }
-
   // Vote to disable Aero composited desktop effects while capturing. Windows
   // will restore Aero automatically if the process exits. This has no effect
   // under Windows 8 or higher.  See crbug.com/124018.
   if (composition_func_ != NULL) {
     (*composition_func_)(DWM_EC_DISABLECOMPOSITION);
   }
 }
 
 void ScreenCapturerWin::Stop() {
   // Restore Aero.
@@ skipping 295 matching lines @@
     uint32 size) {
   return scoped_refptr<SharedBuffer>();
 }
 
 void ScreenCapturer::Delegate::ReleaseSharedBuffer(
     scoped_refptr<SharedBuffer> buffer) {
 }
 
 // static
 scoped_ptr<ScreenCapturer> ScreenCapturer::Create() {
-  return scoped_ptr<ScreenCapturer>(new ScreenCapturerWin());
+  return CreateWithDisableAero(true);
+}
+
+// static
+scoped_ptr<ScreenCapturer> ScreenCapturer::CreateWithDisableAero(
+    bool disable_aero) {
+  return scoped_ptr<ScreenCapturer>(new ScreenCapturerWin(disable_aero));
 }
 
 }  // namespace media