Extensions: Add metrics to distinguish between the different kinds of declarative API function call…

tools/metrics/histograms/enums.xml

Index: tools/metrics/histograms/enums.xml
diff --git a/tools/metrics/histograms/enums.xml b/tools/metrics/histograms/enums.xml
index a436e7059964d95eb88fe0ec9442fff5977e65e9..666995b9719f31c29be1a98005aa2ced1f3b582b 100644
--- a/tools/metrics/histograms/enums.xml
+++ b/tools/metrics/histograms/enums.xml
@@ -6856,6 +6856,18 @@ uploading your change for review.  These are checked by presubmit scripts.
   <int value="40" label="LargeIconService"/>
 </enum>
 
+<enum name="DeclarativeAPIFunctionCallType" type="int">
+  <int value="0" label="DECLARATIVE_CONTENT_ADD_RULES"/>
+  <int value="1" label="DECLARATIVE_CONTENT_REMOVE_RULES"/>
+  <int value="2" label="DECLARATIVE_CONTENT_GET_RULES"/>
+  <int value="3" label="DECLARATIVE_WEB_REQUEST_ADD_RULES"/>
+  <int value="4" label="DECLARATIVE_WEB_REQUEST_REMOVE_RULES"/>
+  <int value="5" label="DECLARATIVE_WEB_REQUEST_GET_RULES"/>
+  <int value="6" label="DECLARATIVE_WEB_REQUEST_WEBVIEW_ADD_RULES"/>
+  <int value="7" label="DECLARATIVE_WEB_REQUEST_WEBVIEW_REMOVE_RULES"/>
+  <int value="8" label="DECLARATIVE_WEB_REQUEST_WEBVIEW_GET_RULES"/>
+</enum>
+
 <enum name="DecodedImageOrientation" type="int">
   <int value="0" label="Unknown"/>
   <int value="1" label="Top Left"/>