Telemetry support for iframes.

tools/telemetry/telemetry/core/web_contents.py

Index: tools/telemetry/telemetry/core/web_contents.py
diff --git a/tools/telemetry/telemetry/core/web_contents.py b/tools/telemetry/telemetry/core/web_contents.py
index 1837a301ca728e74ca6f8e4d79be33d48c53d4e2..15c87e89f9ee173577f2b02cf1339b3de0c5979f 100644
--- a/tools/telemetry/telemetry/core/web_contents.py
+++ b/tools/telemetry/telemetry/core/web_contents.py
@@ -73,7 +73,8 @@ class WebContents(object):
 
     If the expression failed to evaluate, EvaluateException will be raised.
     """
-    self._inspector_backend.ExecuteJavaScript(expr, timeout)
+    return self.ExecuteJavaScriptInContext(
+        expr, context_id=None, timeout=timeout)
 
   def EvaluateJavaScript(self, expr, timeout=DEFAULT_WEB_CONTENTS_TIMEOUT):
     """Evalutes expr in JavaScript and returns the JSONized result.
@@ -87,7 +88,24 @@ class WebContents(object):
     If the result of the evaluation cannot be JSONized, then an
     EvaluationException will be raised.
     """
-    return self._inspector_backend.EvaluateJavaScript(expr, timeout)
+    return self.EvaluateJavaScriptInContext(
+        expr, context_id=None, timeout=timeout)
+
+  def ExecuteJavaScriptInContext(self, expr, context_id,
+                                 timeout=DEFAULT_WEB_CONTENTS_TIMEOUT):
+    """Similar to ExecuteJavaScript, except context_id can refer to an iframe.
+    The main page has context_id=1, the first iframe context_id=2, etc.
+    """
+    return self._inspector_backend.ExecuteJavaScript(
+        expr, context_id=context_id, timeout=timeout)
+
+  def EvaluateJavaScriptInContext(self, expr, context_id,
+                                  timeout=DEFAULT_WEB_CONTENTS_TIMEOUT):
+    """Similar to ExecuteJavaScript, except context_id can refer to an iframe.
+    The main page has context_id=1, the first iframe context_id=2, etc.
+    """
+    return self._inspector_backend.EvaluateJavaScript(
+        expr, context_id=context_id, timeout=timeout)
 
   @property
   def message_output_stream(self):