Add detailed histograms for navigator.share.

chrome/android/java/src/org/chromium/chrome/browser/webshare/ShareServiceImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/webshare/ShareServiceImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webshare/ShareServiceImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/webshare/ShareServiceImpl.java
index df32f4f7592f4a3ba421fcab731ab7044ef528fe..f49b85010197454f3967602b4b0e39ad6b629b2c 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webshare/ShareServiceImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webshare/ShareServiceImpl.java
@@ -8,6 +8,7 @@ import android.app.Activity;
 import android.content.ComponentName;
 import android.support.annotation.Nullable;
 
+import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.chrome.browser.share.ShareHelper;
 import org.chromium.content.browser.ContentViewCore;
 import org.chromium.content_public.browser.WebContents;
@@ -23,6 +24,20 @@ import org.chromium.ui.base.WindowAndroid;
 public class ShareServiceImpl implements ShareService {
     private final Activity mActivity;
 
+    // These numbers are written to histograms. Keep in sync with WebShareMethod enum in
+    // histograms.xml, and don't reuse or renumber entries (except for the _COUNT entry).
+    private static final int WEBSHARE_METHOD_SHARE = 0;
+    // Count is technically 1, but recordEnumeratedHistogram requires a boundary of at least 2
+    // (https://crbug.com/645032).
+    private static final int WEBSHARE_METHOD_COUNT = 2;
+
+    // These numbers are written to histograms. Keep in sync with WebShareOutcome enum in
+    // histograms.xml, and don't reuse or renumber entries (except for the _COUNT entry).
+    private static final int WEBSHARE_OUTCOME_SUCCESS = 0;
+    private static final int WEBSHARE_OUTCOME_UNKNOWN_FAILURE = 1;
+    private static final int WEBSHARE_OUTCOME_CANCELED = 2;
+    private static final int WEBSHARE_OUTCOME_COUNT = 3;
+
     public ShareServiceImpl(@Nullable WebContents webContents) {
         mActivity = activityFromWebContents(webContents);
     }
@@ -35,17 +50,26 @@ public class ShareServiceImpl implements ShareService {
 
     @Override
     public void share(String title, String text, Url url, final ShareResponse callback) {
+        RecordHistogram.recordEnumeratedHistogram("WebShare.ApiCount", WEBSHARE_METHOD_SHARE,
+                WEBSHARE_METHOD_COUNT);
+
         if (mActivity == null) {
+            RecordHistogram.recordEnumeratedHistogram("WebShare.ShareOutcome",
+                    WEBSHARE_OUTCOME_UNKNOWN_FAILURE, WEBSHARE_OUTCOME_COUNT);
             callback.call("Share failed");
             return;
         }
 
         ShareHelper.TargetChosenCallback innerCallback = new ShareHelper.TargetChosenCallback() {
             public void onTargetChosen(ComponentName chosenComponent) {
+                RecordHistogram.recordEnumeratedHistogram("WebShare.ShareOutcome",
+                        WEBSHARE_OUTCOME_SUCCESS, WEBSHARE_OUTCOME_COUNT);
                 callback.call(null);
             }
 
             public void onCancel() {
+                RecordHistogram.recordEnumeratedHistogram("WebShare.ShareOutcome",
+                        WEBSHARE_OUTCOME_CANCELED, WEBSHARE_OUTCOME_COUNT);
                 callback.call("Share canceled");
             }
         };