Adding a flag for drawing the cursor to the RenderData class.

With the introduction of new input modes, we need to be able to figure
out whether the current input strategy wants the local cursor bitmap
to be rendered or not.

I have added this attribute to the RenderData class which is set by the
InputStrategy when it is instantiated and read by the DesktopView during
each render loop.

This change was pulled from a larger CL.  The original impl had this
flag in the DesktopView class instead with a suggestion of making it
volatile or an AtomicBoolean.  This flag will be changed a handful of
times a session but read many thousands of times.  Therefore I did not
want to add overhead to the read operation that would come from the
volatile/AtomicBoolean approach.  Instead I want to use the mRenderData
sync mechanism (which is already acquired within the render loop) so no
overhead is added.

BUG=

Review URL: https://codereview.chromium.org/1514453006

Cr-Commit-Position: refs/heads/master@{#364182}

3 files changed, 19 insertions, 5 deletions

diff --git a/remoting/android/java/src/org/chromium/chromoting/DesktopView.java b/remoting/android/java/src/org/chromium/chromoting/DesktopView.java
index 5d015e5..5d4e33d 100644
--- a/remoting/android/java/src/org/chromium/chromoting/DesktopView.java
+++ b/remoting/android/java/src/org/chromium/chromoting/DesktopView.java
@@ -233,6 +233,7 @@ public class DesktopView extends SurfaceView implements DesktopViewInterface,
 
         Canvas canvas;
         Point cursorPosition;
+        boolean drawCursor;
         synchronized (mRenderData) {
             mRepaintPending = false;
             // Don't try to lock the canvas before it is ready, as the implementation of
@@ -247,6 +248,7 @@ public class DesktopView extends SurfaceView implements DesktopViewInterface,
                 return;
             }
             canvas.setMatrix(mRenderData.transform);
+            drawCursor = mRenderData.drawCursor;
             cursorPosition = mRenderData.getCursorPosition();
         }
 
@@ -263,11 +265,13 @@ public class DesktopView extends SurfaceView implements DesktopViewInterface,
             mFeedbackAnimator.render(canvas, cursorPosition.x, cursorPosition.y, scaleFactor);
         }
 
-        Bitmap cursorBitmap = JniInterface.getCursorBitmap();
-        if (cursorBitmap != null) {
-            Point hotspot = JniInterface.getCursorHotspot();
-            canvas.drawBitmap(cursorBitmap, cursorPosition.x - hotspot.x,
-                    cursorPosition.y - hotspot.y, new Paint());
+        if (drawCursor) {
+            Bitmap cursorBitmap = JniInterface.getCursorBitmap();
+            if (cursorBitmap != null) {
+                Point hotspot = JniInterface.getCursorHotspot();
+                canvas.drawBitmap(cursorBitmap, cursorPosition.x - hotspot.x,
+                        cursorPosition.y - hotspot.y, new Paint());
+            }
         }
 
         getHolder().unlockCanvasAndPost(canvas);
@@ -427,5 +431,8 @@ public class DesktopView extends SurfaceView implements DesktopViewInterface,
                 // Unreachable, but required by Google Java style and findbugs.
                 assert false : "Unreached";
         }
+
+        // Ensure the cursor state is updated appropriately.
+        requestRepaint();
     }
 }
diff --git a/remoting/android/java/src/org/chromium/chromoting/RenderData.java b/remoting/android/java/src/org/chromium/chromoting/RenderData.java
index 50d7217..8e21488 100644
--- a/remoting/android/java/src/org/chromium/chromoting/RenderData.java
+++ b/remoting/android/java/src/org/chromium/chromoting/RenderData.java
@@ -20,6 +20,9 @@ public class RenderData {
     public int imageWidth = 0;
     public int imageHeight = 0;
 
+    /** Determines whether the local cursor should be drawn. */
+    public boolean drawCursor = false;
+
     /**
      * Specifies the position, in image coordinates, at which the cursor image will be drawn.
      * This will normally be at the location of the most recently injected motion event.
diff --git a/remoting/android/java/src/org/chromium/chromoting/TrackpadInputStrategy.java b/remoting/android/java/src/org/chromium/chromoting/TrackpadInputStrategy.java
index b992124..326eff9 100644
--- a/remoting/android/java/src/org/chromium/chromoting/TrackpadInputStrategy.java
+++ b/remoting/android/java/src/org/chromium/chromoting/TrackpadInputStrategy.java
@@ -22,6 +22,10 @@ public class TrackpadInputStrategy implements InputStrategyInterface {
 
     public TrackpadInputStrategy(RenderData renderData) {
         mRenderData = renderData;
+
+        synchronized (mRenderData) {
+            mRenderData.drawCursor = true;
+        }
     }
 
     @Override