Implement DrawImage using Drawee

Summary: Alternative implementation of DrawImage using DraweeHierarchy instead of ImagePipeline directly. Yields same results, but potentially more stable. We'll run tests to measure performance of both.

Reviewed By: ahmedre

Differential Revision: D2746197

ReactAndroid/src/main/java/com/facebook/react/flat/DraweeRequestHelper.java

@@ -0,0 +1,73 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package com.facebook.react.flat;
+
+
+import android.content.res.Resources;
+import android.graphics.drawable.Drawable;
+
+import com.facebook.drawee.controller.AbstractDraweeControllerBuilder;
+import com.facebook.drawee.generic.GenericDraweeHierarchy;
+import com.facebook.drawee.generic.GenericDraweeHierarchyBuilder;
+import com.facebook.drawee.interfaces.DraweeController;
+import com.facebook.drawee.interfaces.DraweeController;
+import com.facebook.imagepipeline.request.ImageRequest;
+import com.facebook.infer.annotation.Assertions;
+
+/* package */ final class DraweeRequestHelper {
+
+  private static GenericDraweeHierarchyBuilder sHierarchyBuilder;
+  private static AbstractDraweeControllerBuilder sControllerBuilder;
+
+  /* package */ static void setResources(Resources resources) {
+    sHierarchyBuilder = new GenericDraweeHierarchyBuilder(resources);
+  }
+
+  /* package */ static void setDraweeControllerBuilder(AbstractDraweeControllerBuilder builder) {
+    sControllerBuilder = builder;
+  }
+
+  private final DraweeController mDraweeController;
+  private int mAttachCounter;
+
+  /* package */ DraweeRequestHelper(ImageRequest imageRequest) {
+    DraweeController controller = sControllerBuilder
+          .setImageRequest(imageRequest)
+          .setCallerContext(RCTImageView.getCallerContext())
+          .build();
+
+    controller.setHierarchy(sHierarchyBuilder.build());
+
+    mDraweeController = controller;
+  }
+
+  /* package */ void attach(FlatViewGroup.InvalidateCallback callback) {
+    ++mAttachCounter;
+    if (mAttachCounter == 1) {
+      getDrawable().setCallback(callback.get());
+      mDraweeController.onAttach();
+    }
+  }
+
+  /* package */ void detach() {
+    --mAttachCounter;
+    if (mAttachCounter == 0) {
+      mDraweeController.onDetach();
+    }
+  }
+
+  /* package */ GenericDraweeHierarchy getHierarchy() {
+    return (GenericDraweeHierarchy) Assertions.assumeNotNull(mDraweeController.getHierarchy());
+  }
+
+  /* package */ Drawable getDrawable() {
+    return getHierarchy().getTopLevelDrawable();
+  }
+}