Image decode color: Push color profile from browser to renderer

ui/gfx/color_profile.h

 // 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.
 
 #ifndef UI_GFX_COLOR_PROFILE_H_
 #define UI_GFX_COLOR_PROFILE_H_
 
 #include <stddef.h>
 
 #include <vector>
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/gfx_export.h"
 #include "ui/gfx/native_widget_types.h"
 
 namespace gfx {
 
 static const size_t kMinProfileLength = 128;
 static const size_t kMaxProfileLength = 4 * 1024 * 1024;
 
 class GFX_EXPORT ColorProfile {
  public:
-  // On Windows, this reads a file from disk so it should not be run on the UI
-  // or IO thread.
+  // Creates a color profile for the system's primary monitor.

[ccameron, 2016/03/15 06:02:24]

This should be a function called GetPrimaryDisplayColorProfile(), not a default
constructor.

I will fix that in the upcoming refactor (for now, I'm leaving it as-is, modulo
allowing IO/UI thread access because Windows is now reading cached data).

   ColorProfile();
   ~ColorProfile();
 
   const std::vector<char>& profile() const { return profile_; }
 
  private:
   std::vector<char> profile_;
 
   DISALLOW_COPY_AND_ASSIGN(ColorProfile);
 };
 
 inline bool InvalidColorProfileLength(size_t length) {
   return (length < kMinProfileLength) || (length > kMaxProfileLength);
 }
 
-// Return the color profile of the display nearest the screen bounds. On Win32,
-// this may read a file from disk so it should not be run on the UI/IO threads.
-// If the given bounds are empty, or are off-screen, return false meaning there
-// is no color profile associated with the bounds.  Otherwise return true after
+#if defined(OS_WIN)
+// On Windows, color profile data is read from a file on disk, which may take an
+// arbitrarily long time to run. This function will update all displays' color
+// profiles. It should not be called on the UI or IO threads. The functions to
+// query color profiles will read the data cached by this function.
+void GFX_EXPORT UpdateDisplayColorProfileCache();
+#endif
+
+// Return the color profile of the display nearest the screen bounds. If the
+// given bounds are empty, or are off-screen, return false meaning there is no
+// color profile associated with the bounds.  Otherwise return true after
 // storing the display's color profile in |profile|, which will be empty if the
 // standard sRGB color profile should be assumed.
 GFX_EXPORT bool GetDisplayColorProfile(const gfx::Rect& bounds,
                                        std::vector<char>* profile);
 #if defined(OS_MACOSX)

[ccameron, 2016/03/15 06:02:24]

Note that there is no reason why Mac should have a separate API here -- when we
merge this with gfx::Screen and gfx::Display, this difference can go away.

[Avi (use Gerrit), 2016/03/15 16:20:38]

woot

 // Return the color profile of the native window. If the window is null, or has
 // empty bounds, return false meaning there is no color profile associated with
 // the window.  Otherwise return true after storing the window color profile in
 // |profile|, which will be empty if the sRGB color profile should be assumed.
 GFX_EXPORT bool GetDisplayColorProfile(gfx::NativeWindow window,
                                        std::vector<char>* profile);
 #endif
 }  // namespace gfx
 
 #endif  // UI_GFX_COLOR_PROFILE_H_