Count document.createEvent() usage

third_party/WebKit/Source/build/scripts/make_event_factory.py

Index: third_party/WebKit/Source/build/scripts/make_event_factory.py
diff --git a/third_party/WebKit/Source/build/scripts/make_event_factory.py b/third_party/WebKit/Source/build/scripts/make_event_factory.py
index aa87658f566846a906dffccc7e3b842533af0a4a..1f280fe05ae3fa981a62ba66feff7dbc14b8dfab 100755
--- a/third_party/WebKit/Source/build/scripts/make_event_factory.py
+++ b/third_party/WebKit/Source/build/scripts/make_event_factory.py
@@ -59,6 +59,41 @@ def case_insensitive_matching(name):
             or name == 'TouchEvent')
 
 
+# All events _not_ on the following whitelist are being measured in

[philipj_slow, 2016/02/11 14:40:28]

I like this approach! But can you reduce the list to just what the spec says? I
think there's some hope that device motion and orientation events could be
excluded from this list, and it would be a practical benefit if the list
eventually only contains things in core/.

(The things you remove should correspond to init*Event() with TODOs, but I may
not have documented all of them properly yet.

+# createEvent. The plan is to limit createEvent to just a few selected
+# events necessary for legacy content according to the specification:
+#
+# https://dom.spec.whatwg.org/#dom-document-createevent
+#
+# The criteria for the current whitelist, unless otherwise noted, is
+# to have a corresponding init*Event() function, or being an alias for
+# an event that has a corresponding init*Event(). It isn't a full
+# match with the spec yet.
+def candidate_whitelist(name):
+    return (name == 'CustomEvent'
+            or name == 'CompositionEvent'
+            or name == 'DeviceMotionEvent'
+            or name == 'DeviceOrientationEvent'
+            or name == 'Event'
+            or name == 'Events'
+            or name == 'HTMLEvents'
+            or name == 'KeyboardEvent'
+            or name == 'KeyboardEvents'
+            or name == 'MessageEvent'
+            or name == 'MouseEvent'
+            or name == 'MutationEvent'
+            or name == 'OrientationEvent'
+            or name == 'SVGEvents'
+            or name == 'SVGZoomEvent'  # Will be deprecated instead.
+            or name == 'StorageEvent'
+            or name == 'TextEvent'
+            or name == 'TouchEvent'
+            or name == 'UIEvent')
+
+
+def measure_name(name):
+    return 'DocumentCreateEvent' + name
+
 class EventFactoryWriter(in_generator.Writer):
     defaults = {
         'ImplementedAs': None,
@@ -74,6 +109,8 @@ class EventFactoryWriter(in_generator.Writer):
         'lower_first': name_utilities.lower_first,
         'case_insensitive_matching': case_insensitive_matching,
         'script_name': name_utilities.script_name,
+        'candidate_whitelist': candidate_whitelist,
+        'measure_name': measure_name,
     }
 
     def __init__(self, in_file_path):