Use relocated SkImages context typedef

In http://review.skia.org/661059, we moved many SkImage related
methods, including these typedefs. This updates android/base to
use that moved type.

Change-Id: I8ace594ed19561516bef4468cca0bf59a2910483
diff --git a/libs/hwui/AutoBackendTextureRelease.cpp b/libs/hwui/AutoBackendTextureRelease.cpp
index ab85995..b796585 100644
--- a/libs/hwui/AutoBackendTextureRelease.cpp
+++ b/libs/hwui/AutoBackendTextureRelease.cpp
@@ -72,7 +72,7 @@
 
 // releaseProc is invoked by SkImage, when texture is no longer in use.
 // "releaseContext" contains an "AutoBackendTextureRelease*".
-static void releaseProc(SkImage::ReleaseContext releaseContext) {
+static void releaseProc(SkImages::ReleaseContext releaseContext) {
     AutoBackendTextureRelease* textureRelease =
             reinterpret_cast<AutoBackendTextureRelease*>(releaseContext);
     textureRelease->unref(false);