[Android] Photo Picker: Add a simple RenderTest.

The test selects the first photo, scrolls to the bottom and back up
to the top to make sure the selection border is active and of correct
size (old bug I encountered once).

This should also function as a regression test for bugs like the one
seen in issue 1051523 (where a white circle got overlaid on top of
all photos).

Bug: 1051523, 656015
Change-Id: Ifb119c5e9450be5ef06b303eb3549315c0e4a623
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2083178
Commit-Queue: Finnur Thorarinsson <finnur@chromium.org>
Reviewed-by: Boris Sazonov <bsazonov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#747188}

chrome/android/java/src/org/chromium/chrome/browser/photo_picker/DecoderServiceHost.java

@@ -108,6 +108,11 @@ public class DecoderServiceHost
          * A function to define to receive a notification once the service is up and running.
          */
         void serviceReady();
+
+        /**
+         * Called when the decoder is idle.
+         */
+        void decoderIdle();
     }
 
     /**
@@ -340,6 +345,10 @@ public class DecoderServiceHost
             mFailedVideoDecodesIo = 0;
             mFailedVideoDecodesUnknown = 0;
         }
+
+        for (DecoderStatusCallback callback : mCallbacks) {
+            callback.decoderIdle();
+        }
     }
 
     /**

chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java

@@ -341,6 +341,9 @@ public class PickerCategoryView extends RelativeLayout
         processBitmaps();
     }
 
+    @Override
+    public void decoderIdle() {}
+
     // RecyclerView.RecyclerListener:
 
     @Override

chrome/android/javatests/src/org/chromium/chrome/browser/photo_picker/DecoderServiceHostTest.java

@@ -49,10 +49,10 @@ public class DecoderServiceHostTest implements DecoderServiceHost.DecoderStatusC
     private Context mContext;
 
     // A callback that fires when the decoder is ready.
-    public final CallbackHelper onDecoderReadyCallback = new CallbackHelper();
+    public final CallbackHelper mOnDecoderReadyCallback = new CallbackHelper();
 
     // A callback that fires when something is finished decoding in the dialog.
-    public final CallbackHelper onDecodedCallback = new CallbackHelper();
+    public final CallbackHelper mOnDecodedCallback = new CallbackHelper();
 
     private String mLastDecodedPath;
     private boolean mLastIsVideo;
@@ -73,9 +73,12 @@ public class DecoderServiceHostTest implements DecoderServiceHost.DecoderStatusC
 
     @Override
     public void serviceReady() {
-        onDecoderReadyCallback.notifyCalled();
+        mOnDecoderReadyCallback.notifyCalled();
     }
 
+    @Override
+    public void decoderIdle() {}
+
     // DecoderServiceHost.ImagesDecodedCallback:
 
     @Override
@@ -88,18 +91,18 @@ public class DecoderServiceHostTest implements DecoderServiceHost.DecoderStatusC
         mLastVideoDuration = videoDuration;
         mLastRatio = ratio;
 
-        onDecodedCallback.notifyCalled();
+        mOnDecodedCallback.notifyCalled();
     }
 
     private void waitForDecoder() throws Exception {
-        int callCount = onDecoderReadyCallback.getCallCount();
-        onDecoderReadyCallback.waitForCallback(
+        int callCount = mOnDecoderReadyCallback.getCallCount();
+        mOnDecoderReadyCallback.waitForCallback(
                 callCount, 1, WAIT_TIMEOUT_SECONDS, TimeUnit.SECONDS);
     }
 
     private void waitForThumbnailDecode() throws Exception {
-        int callCount = onDecodedCallback.getCallCount();
-        onDecodedCallback.waitForCallback(callCount, 1, WAIT_TIMEOUT_SECONDS, TimeUnit.SECONDS);
+        int callCount = mOnDecodedCallback.getCallCount();
+        mOnDecodedCallback.waitForCallback(callCount, 1, WAIT_TIMEOUT_SECONDS, TimeUnit.SECONDS);
     }
 
     private void decodeImage(DecoderServiceHost host, Uri uri, @PickerBitmap.TileTypes int fileType,

chrome/test/data/android/render_tests/PhotoPickerDialogTest.first_view_clicked.Nexus_5X-23.png.sha1

+712be6658684375f38d598a119343b391acdffde
\ No newline at end of file

chrome/test/data/android/render_tests/PhotoPickerDialogTest.initial_load.Nexus_5X-23.png.sha1

+45dd2fd26f943d60d1b4bb4f113fbe7c2c69bd00
\ No newline at end of file