diff -r 000000000000 -r 6474c204b198 widget/windows/nsColorPicker.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/windows/nsColorPicker.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,173 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsColorPicker.h"
+
+#include <shlwapi.h>
+
+#include "mozilla/AutoRestore.h"
+#include "nsIWidget.h"
+#include "WidgetUtils.h"
+
+using namespace mozilla::widget;
+
+namespace
+{
+// Manages NS_NATIVE_TMP_WINDOW child windows. NS_NATIVE_TMP_WINDOWs are
+// temporary child windows of mParentWidget created to address RTL issues
+// in picker dialogs. We are responsible for destroying these.
+class AutoDestroyTmpWindow
+{
+public:
+  explicit AutoDestroyTmpWindow(HWND aTmpWnd) :
+    mWnd(aTmpWnd) {
+  }
+
+  ~AutoDestroyTmpWindow() {
+    if (mWnd)
+      DestroyWindow(mWnd);
+  }
+
+  inline HWND get() const { return mWnd; }
+private:
+  HWND mWnd;
+};
+
+static DWORD ColorStringToRGB(const nsAString& aColor)
+{
+  DWORD result = 0;
+
+  for (uint32_t i = 1; i < aColor.Length(); ++i) {
+    result *= 16;
+
+    char16_t c = aColor[i];
+    if (c >= '0' && c <= '9') {
+      result += c - '0';
+    } else if (c >= 'a' && c <= 'f') {
+      result += 10 + (c - 'a');
+    } else {
+      result += 10 + (c - 'A');
+    }
+  }
+
+  DWORD r = result & 0x00FF0000;
+  DWORD g = result & 0x0000FF00;
+  DWORD b = result & 0x000000FF;
+
+  r = r >> 16;
+  b = b << 16;
+
+  result = r | g | b;
+
+  return result;
+}
+
+static nsString ToHexString(BYTE n)
+{
+  nsString result;
+  if (n <= 0x0F) {
+    result.Append('0');
+  }
+  result.AppendInt(n, 16);
+  return result;
+}
+
+
+static void
+BGRIntToRGBString(DWORD color, nsAString& aResult)
+{
+  BYTE r = GetRValue(color);
+  BYTE g = GetGValue(color);
+  BYTE b = GetBValue(color);
+
+  aResult.AssignLiteral("#");
+  aResult.Append(ToHexString(r));
+  aResult.Append(ToHexString(g));
+  aResult.Append(ToHexString(b));
+}
+} // anonymous namespace
+
+AsyncColorChooser::AsyncColorChooser(const nsAString& aInitialColor,
+                                     nsIWidget* aParentWidget,
+                                     nsIColorPickerShownCallback* aCallback)
+  : mInitialColor(aInitialColor)
+  , mParentWidget(aParentWidget)
+  , mCallback(aCallback)
+{
+}
+
+NS_IMETHODIMP
+AsyncColorChooser::Run()
+{
+  static COLORREF sCustomColors[16] = {0} ;
+
+  MOZ_ASSERT(NS_IsMainThread(),
+      "Color pickers can only be opened from main thread currently");
+
+  static bool sColorPickerOpen = false;
+  // Allow only one color picker to be opened at a time, to workaround bug 944737
+  if (!sColorPickerOpen) {
+    mozilla::AutoRestore<bool> autoRestoreColorPickerOpen(sColorPickerOpen);
+    sColorPickerOpen = true;
+
+    AutoDestroyTmpWindow adtw((HWND) (mParentWidget.get() ?
+      mParentWidget->GetNativeData(NS_NATIVE_TMP_WINDOW) : nullptr));
+
+    CHOOSECOLOR options;
+    options.lStructSize   = sizeof(options);
+    options.hwndOwner     = adtw.get();
+    options.Flags         = CC_RGBINIT | CC_FULLOPEN;
+    options.rgbResult     = ColorStringToRGB(mInitialColor);
+    options.lpCustColors  = sCustomColors;
+
+    if (ChooseColor(&options)) {
+      BGRIntToRGBString(options.rgbResult, mColor);
+    }
+  } else {
+    NS_WARNING("Currently, it's not possible to open more than one color "
+               "picker at a time");
+    mColor = mInitialColor;
+  }
+
+  if (mCallback) {
+    mCallback->Done(mColor);
+  }
+
+  return NS_OK;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// nsIColorPicker
+
+nsColorPicker::nsColorPicker()
+{
+}
+
+nsColorPicker::~nsColorPicker()
+{
+}
+
+NS_IMPL_ISUPPORTS(nsColorPicker, nsIColorPicker)
+
+NS_IMETHODIMP
+nsColorPicker::Init(nsIDOMWindow* parent,
+                    const nsAString& title,
+                    const nsAString& aInitialColor)
+{
+  NS_PRECONDITION(parent,
+      "Null parent passed to colorpicker, no color picker for you!");
+  mParentWidget =  WidgetUtils::DOMWindowToWidget(parent);
+  mInitialColor = aInitialColor;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsColorPicker::Open(nsIColorPickerShownCallback* aCallback)
+{
+  NS_ENSURE_ARG(aCallback);
+  nsCOMPtr<nsIRunnable> event = new AsyncColorChooser(mInitialColor, mParentWidget, aCallback);
+  return NS_DispatchToMainThread(event);
+}