Migrate some last instances of GrContext to GrDirectContext

This is a rename with no functional changes.

Change-Id: I4b0b7ee1926b688029e257b35c469113c0404a5b
diff --git a/libs/hwui/renderthread/CacheManager.cpp b/libs/hwui/renderthread/CacheManager.cpp
index b57dee4..85924c5 100644
--- a/libs/hwui/renderthread/CacheManager.cpp
+++ b/libs/hwui/renderthread/CacheManager.cpp
@@ -61,7 +61,7 @@
     SkGraphics::SetFontCacheLimit(mMaxCpuFontCacheBytes);
 }
 
-void CacheManager::reset(sk_sp<GrContext> context) {
+void CacheManager::reset(sk_sp<GrDirectContext> context) {
     if (context != mGrContext) {
         destroy();
     }