Add support for RCTText under FlatUIImplementation

Summary: @public Initial version of FlatUIImplementation lacks any primitives support (such as RCTText, RCTImageView or RCTView). This diff add the first part, RCTText (alongside with RCTVirtualText and RCTRawText).

Reviewed By: sriramramani

Differential Revision: D2693348

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

@@ -0,0 +1,88 @@
+/**
+ * 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 com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.uimanager.UIViewOperationQueue;
+
+/**
+ * FlatUIViewOperationQueue extends {@link UIViewOperationQueue} to add
+ * FlatUIImplementation-specific methods that need to run in UI thread.
+ */
+/* package */ final class FlatUIViewOperationQueue extends UIViewOperationQueue {
+
+  private final FlatNativeViewHierarchyManager mNativeViewHierarchyManager;
+
+  /**
+   * UIOperation that updates DrawCommands for a View defined by reactTag.
+   */
+  private final class UpdateMountState implements UIOperation {
+
+    private final int mReactTag;
+    private final DrawCommand[] mDrawCommands;
+
+    private UpdateMountState(int reactTag, DrawCommand[] drawCommands) {
+      mReactTag = reactTag;
+      mDrawCommands = drawCommands;
+    }
+
+    @Override
+    public void execute() {
+      mNativeViewHierarchyManager.updateMountState(mReactTag, mDrawCommands);
+    }
+  }
+
+  /**
+   * UIOperation that updates View bounds for a View defined by reactTag.
+   */
+  private final class UpdateViewBounds implements UIOperation {
+
+    private final int mReactTag;
+    private final int mLeft;
+    private final int mTop;
+    private final int mRight;
+    private final int mBottom;
+
+    private UpdateViewBounds(int reactTag, int left, int top, int right, int bottom) {
+      mReactTag = reactTag;
+      mLeft = left;
+      mTop = top;
+      mRight = right;
+      mBottom = bottom;
+    }
+
+    @Override
+    public void execute() {
+      mNativeViewHierarchyManager.updateViewBounds(mReactTag, mLeft, mTop, mRight, mBottom);
+    }
+  }
+
+  public FlatUIViewOperationQueue(
+      ReactApplicationContext reactContext,
+      FlatNativeViewHierarchyManager nativeViewHierarchyManager) {
+    super(reactContext, nativeViewHierarchyManager);
+
+    mNativeViewHierarchyManager = nativeViewHierarchyManager;
+  }
+
+  /**
+   * Enqueues a new UIOperation that will update DrawCommands for a View defined by reactTag.
+   */
+  public void enqueueUpdateMountState(int reactTag, DrawCommand[] drawCommands) {
+    enqueueUIOperation(new UpdateMountState(reactTag, drawCommands));
+  }
+
+  /**
+   * Enqueues a new UIOperation that will update View bounds for a View defined by reactTag.
+   */
+  public void enqueueUpdateViewBounds(int reactTag, int left, int top, int right, int bottom) {
+    enqueueUIOperation(new UpdateViewBounds(reactTag, left, top, right, bottom));
+  }
+}