[Mac] Implement a new WebSandboxSupport method to get the display's color space.

content/renderer/renderer_webkitplatformsupport_impl.cc

Index: content/renderer/renderer_webkitplatformsupport_impl.cc
diff --git a/content/renderer/renderer_webkitplatformsupport_impl.cc b/content/renderer/renderer_webkitplatformsupport_impl.cc
index 797285fc125d7174fbad4aca78548e04c28492f9..e607b5c3e3ff83ad21d0b9932ed7925bc64e3746 100644
--- a/content/renderer/renderer_webkitplatformsupport_impl.cc
+++ b/content/renderer/renderer_webkitplatformsupport_impl.cc
@@ -84,6 +84,7 @@
 #endif
 
 #if defined(OS_MACOSX)
+#include "base/mac/mac_util.h"
 #include "content/common/mac/font_descriptor.h"
 #include "content/common/mac/font_loader.h"
 #include "content/renderer/webscrollbarbehavior_impl_mac.h"
@@ -202,6 +203,7 @@ class RendererWebKitPlatformSupportImpl::SandboxSupport
       NSFont* src_font,
       CGFontRef* container,
       uint32* font_id);
+  virtual CGColorSpaceRef displayColorSpace();
 #elif defined(OS_POSIX)
   virtual void getFallbackFontForCharacter(
       blink::WebUChar32 character,
@@ -573,6 +575,11 @@ bool RendererWebKitPlatformSupportImpl::SandboxSupport::loadFont(
   return FontLoader::CGFontRefFromBuffer(font_data, font_data_size, out);
 }
 
+CGColorSpaceRef
+RendererWebKitPlatformSupportImpl::SandboxSupport::displayColorSpace() {
+  return base::mac::GetSystemColorSpace();

[Noel Gordon, 2014/09/10 07:35:37]

This could be called on an arbitrary thread, such as an impl-side-painting
thread for example.  Are we thread-safe here?

Also, what color profile does this return (aka for which screen)?

(Sorry to ask these question, but the the change description doesn't tell me why
we're making this change).

[Noel Gordon, 2014/09/10 07:52:50]

And it seems we're not; the other code review 

https://codereview.chromium.org/554033002

appears to be crashing image decoder unit tests, which is new.

[Robert Sesek, 2014/09/10 14:34:12]

That has nothing to do with thread safety. There's no sandboxSupport in webkit
tests. Yes, this is thread safe. It's also identical to what gfx::ColorProfile's
ctor does.

+}
+
 #elif defined(OS_ANDROID)
 
 // WebKit doesn't use WebSandboxSupport on android so we don't need to