color: Fix accidental partial color conversion

ui/gfx/color_transform.cc

Index: ui/gfx/color_transform.cc
diff --git a/ui/gfx/color_transform.cc b/ui/gfx/color_transform.cc
index 1d562d48401ec84c1b60a4d3f80bfb59954f310a..e6d8907a96c48b4e95bbdf0d3c8b457994638ffb 100644
--- a/ui/gfx/color_transform.cc
+++ b/ui/gfx/color_transform.cc
@@ -732,8 +732,14 @@ ColorTransformInternal::ColorTransformInternal(const ColorSpace& src,
   if (!src_.IsValid())
     return;
 
-  ScopedQcmsProfile src_profile = GetQCMSProfileIfNecessary(src_);
-  ScopedQcmsProfile dst_profile = GetQCMSProfileIfNecessary(dst_);
+  // If the dst profile is not set, then do only YUV to RGB conversion, so

[hubbe, 2017/02/21 22:46:49]

I'm afraid I don't get this.
When does this happen?

[ccameron, 2017/02/22 00:08:29]

This happens whenever media::kVideoColorManagement is not true and color
conversion is not enabled.

In that case we have ColorTransform do the YUV->RGB conversion for us (instead
of doing it manually in GLRenderer).

[hubbe, 2017/02/22 00:10:05]

Can we add some more meat to the comment to describe this?

[ccameron, 2017/02/22 00:30:48]

Done.

+  // ignore any ICC profiles.
+  ScopedQcmsProfile src_profile;
+  ScopedQcmsProfile dst_profile;
+  if (dst.IsValid()) {
+    src_profile = GetQCMSProfileIfNecessary(src_);
+    dst_profile = GetQCMSProfileIfNecessary(dst_);
+  }
   bool has_src_profile = !!src_profile;
   bool has_dst_profile = !!dst_profile;