Add metrics to track Google Play install WebAPK failures.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 5e39c18450c4ece79ba0f4cf152aec9892a748fa..ff9421e6f36636e7f3e448be9ecdb7442053f961 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -76099,6 +76099,17 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="WebApk.Install.GooglePlayInstallResult"
+    enum="WebApkGooglePlayInstallResult">
+  <owner>hanxi@chromium.org</owner>
+  <owner>pkotwicz@chromium.org</owner>
+  <owner>yfriedman@chromium.org</owner>
+  <summary>
+    Records whether installing a WebAPK from Google Play succeeded. If not,
+    records the reason that the install failed.
+  </summary>
+</histogram>
+
 <histogram name="WebApk.Install.GooglePlayInstallState"
     enum="WebApkGooglePlayInstallState">
   <owner>hanxi@chromium.org</owner>
@@ -113438,6 +113449,20 @@ from previous Chrome versions.
   <int value="4" label="Session, Warmup"/>
 </enum>
 
+<enum name="WebApkGooglePlayInstallResult" type="int">
+  <int value="0" label="Success"/>
+  <int value="1" label="Install delegate unavailable"/>
+  <int value="2" label="Failed to connect to Google Play Install Service"/>
+  <int value="3" label="Caller verification failure"/>
+  <int value="4" label="Policy violation"/>
+  <int value="5" label="Play install API disabled"/>
+  <int value="6" label="Request to Play install API failed"/>
+  <int value="7" label="Download cancelled"/>
+  <int value="8" label="Download error"/>
+  <int value="9" label="Install error"/>
+  <int value="10" label="Install timed out"/>
+</enum>
+
 <enum name="WebApkGooglePlayInstallState" type="int">
   <int value="0" label="Play installation supported."/>
   <int value="1" label="Play installation disabled for other reason."/>