Improve activity log ad metrics

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 896431ef7afe147abf5dfe097ed6623207d4f9f3..7514e263091bb2effef14373825720d952878988 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -6036,6 +6036,22 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="Extensions.AdInjection.AdType" enum="InjectedAdType">
+  <owner>felt@chromium.org</owner>
+  <owner>rdevlin.cronin@chromium.org</owner>
+  <summary>The type of ad that was injected.</summary>
+</histogram>
+
+<histogram name="Extensions.AdInjection.InstallLocation"
+    enum="ExtensionLocation">
+  <owner>felt@chromium.org</owner>
+  <owner>rdevlin.cronin@chromium.org</owner>
+  <summary>
+    The install location of an ad-injecting extension. Recorded upon page close
+    for any extension that injected ads on that page.
+  </summary>
+</histogram>
+
 <histogram name="Extensions.AllocatePortIdPairOverflow">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <summary>
@@ -36790,6 +36806,13 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="3" label="InfoBar dismissed by clicking the 'X'"/>
 </enum>
 
+<enum name="InjectedAdType" type="int">
+  <int value="0" label="Invalid"/>
+  <int value="1" label="IFrame"/>
+  <int value="2" label="Embed"/>
+  <int value="3" label="Anchor"/>
+</enum>
+
 <enum name="InstantControllerEvent" type="int">
   <int value="0" label="URL_ADDED_TO_BLACKLIST"/>
   <int value="1" label="URL_REMOVED_FROM_BLACKLIST"/>