Add ColorSpace information on Bitmap

This is the first step toward interpreting color spaces at render time.

Bug: 32984164
Test: BitmapColorSpaceTest in CtsGraphicsTestCases

Change-Id: I0164a18f1ed74a745874fe5229168042afe27a04
diff --git a/libs/hwui/GradientCache.h b/libs/hwui/GradientCache.h
index 5e35435..f299a40 100644
--- a/libs/hwui/GradientCache.h
+++ b/libs/hwui/GradientCache.h
@@ -170,7 +170,7 @@
     GLint mMaxTextureSize;
     bool mUseFloatTexture;
     bool mHasNpot;
-    bool mHasSRGB;
+    bool mHasLinearBlending;
 
     mutable Mutex mLock;
 }; // class GradientCache