Photo Picker dialog: Add UMA statistics.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java b/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
index 24bdc226e65f2ba107dbd0408fd2e8f48bb92f06..79c81fa6cb4655501ee0dee7f55ae9934d6a97b9 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
@@ -19,7 +19,9 @@ import android.widget.Button;
 import android.widget.RelativeLayout;
 
 import org.chromium.base.VisibleForTesting;
+import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.chrome.R;
+import org.chromium.chrome.browser.download.DownloadUtils;
 import org.chromium.chrome.browser.widget.selection.SelectableListLayout;
 import org.chromium.chrome.browser.widget.selection.SelectionDelegate;
 import org.chromium.ui.PhotoPickerListener;
@@ -35,7 +37,14 @@ import java.util.List;
 public class PickerCategoryView extends RelativeLayout
         implements FileEnumWorkerTask.FilesEnumeratedCallback, RecyclerView.RecyclerListener,
                    DecoderServiceHost.ServiceReadyCallback, View.OnClickListener {
-    private static final int KILOBYTE = 1024;
+    // Note: these values must match the PhotoPickerDialogAction enum values in histograms.xml.
+    // Only add new values at the end, right before ACTIONS. We depend on these specific values in
+    // UMA histograms.
+    private static final int ACTION_CANCEL = 0;
+    private static final int ACTION_PHOTO_PICKED = 1;
+    private static final int ACTION_NEW_PHOTO = 2;
+    private static final int ACTION_BROWSE = 3;
+    private static final int ACTION_BOUNDARY = 4;
 
     // The dialog that owns us.
     private PhotoPickerDialog mDialog;
@@ -145,7 +154,8 @@ public class PickerCategoryView extends RelativeLayout
         mSpacingDecoration = new GridSpacingItemDecoration(mColumns, mPadding);
         mRecyclerView.addItemDecoration(mSpacingDecoration);
 
-        final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / KILOBYTE);
+        final int maxMemory =
+                (int) (Runtime.getRuntime().maxMemory() / DownloadUtils.BYTES_PER_KILOBYTE);
         final int cacheSizeLarge = maxMemory / 2; // 1/2 of the available memory.
         final int cacheSizeSmall = maxMemory / 8; // 1/8th of the available memory.
         mLowResBitmaps = new LruCache<String, Bitmap>(cacheSizeSmall);
@@ -195,6 +205,7 @@ public class PickerCategoryView extends RelativeLayout
         mDialog.setOnCancelListener(new DialogInterface.OnCancelListener() {
             @Override
             public void onCancel(DialogInterface dialog) {
+                recordFinalUmaStats(ACTION_CANCEL);
                 mListener.onPickerUserAction(PhotoPickerListener.Action.CANCEL, null);
             }
         });
@@ -232,8 +243,10 @@ public class PickerCategoryView extends RelativeLayout
     @Override
     public void onClick(View view) {
         if (view.getId() == R.id.done) {
+            recordFinalUmaStats(ACTION_PHOTO_PICKED);
             notifyPhotosSelected();
         } else {
+            recordFinalUmaStats(ACTION_CANCEL);
             mListener.onPickerUserAction(PhotoPickerListener.Action.CANCEL, null);
         }
 
@@ -284,6 +297,7 @@ public class PickerCategoryView extends RelativeLayout
      * Notifies the listener that the user selected to launch the gallery.
      */
     public void showGallery() {
+        recordFinalUmaStats(ACTION_BROWSE);
         mListener.onPickerUserAction(PhotoPickerListener.Action.LAUNCH_GALLERY, null);
     }
 
@@ -291,6 +305,7 @@ public class PickerCategoryView extends RelativeLayout
      * Notifies the listener that the user selected to launch the camera intent.
      */
     public void showCamera() {
+        recordFinalUmaStats(ACTION_NEW_PHOTO);
         mListener.onPickerUserAction(PhotoPickerListener.Action.LAUNCH_CAMERA, null);
     }
 
@@ -383,6 +398,19 @@ public class PickerCategoryView extends RelativeLayout
         }
     }
 
+    /**
+     * Record UMA statistics (what action was taken in the dialog and other performance stats.

[Theresa, 2017/06/01 15:58:04]

nit: the ( parenthesis is missing a closing parenthesis 

+     * @param action The action the user took in the dialog.
+     */
+    private void recordFinalUmaStats(int action) {
+        RecordHistogram.recordEnumeratedHistogram(
+                "Android.PhotoPicker.DialogAction", action, ACTION_BOUNDARY);
+        RecordHistogram.recordCountHistogram(
+                "Android.PhotoPicker.DecodeRequests", mPickerAdapter.getDecodeRequestCount());
+        RecordHistogram.recordCountHistogram(
+                "Android.PhotoPicker.CacheHits", mPickerAdapter.getCacheHitCount());
+    }
+
     /** Sets a list of files to use as data for the dialog. For testing use only. */
     @VisibleForTesting
     public static void setTestFiles(List<PickerBitmap> testFiles) {