Add SkImage::colorSpace() and SkImage::refColorSpace()

BUG=skia:

Change-Id: I31c2a2731cd70e4e5162905de0ad129516dacc6b
Reviewed-on: https://skia-review.googlesource.com/9152
Commit-Queue: Matt Sarett <msarett@google.com>
Reviewed-by: Mike Reed <reed@google.com>

include/core/SkImage.h

@@ -180,6 +180,16 @@ public:
     uint32_t uniqueID() const { return fUniqueID; }
     SkAlphaType alphaType() const;
 
+    /**
+     *  Returns the color space of the SkImage.
+     *
+     *  This is the color space that was supplied on creation of the SkImage or a color
+     *  space that was parsed from encoded data.  This color space is not guaranteed to be
+     *  renderable.  Can return nullptr if the SkImage was created without a color space.
+     */
+    SkColorSpace* colorSpace() const;
+    sk_sp<SkColorSpace> refColorSpace() const;
+
     /**
      *  Returns true fi the image will be drawn as a mask, with no intrinsic color of its own.
      */

src/image/SkImage.cpp

@@ -82,6 +82,14 @@ SkAlphaType SkImage::alphaType() const {
     return as_IB(this)->onAlphaType();
 }
 
+SkColorSpace* SkImage::colorSpace() const {
+    return as_IB(this)->onImageInfo().colorSpace();
+}
+
+sk_sp<SkColorSpace> SkImage::refColorSpace() const {
+    return as_IB(this)->onImageInfo().refColorSpace();
+}
+
 sk_sp<SkShader> SkImage::makeShader(SkShader::TileMode tileX, SkShader::TileMode tileY,
                                     const SkMatrix* localMatrix) const {
     return SkImageShader::Make(sk_ref_sp(const_cast<SkImage*>(this)), tileX, tileY, localMatrix);