[Telemetry] Add a page set option to use all cold page loads.

tools/telemetry/telemetry/core/chrome/inspector_network.py

Index: tools/telemetry/telemetry/core/chrome/inspector_network.py
diff --git a/tools/telemetry/telemetry/core/chrome/inspector_network.py b/tools/telemetry/telemetry/core/chrome/inspector_network.py
new file mode 100644
index 0000000000000000000000000000000000000000..e533a90f991495805a4d9803fe354784c4bd1c2c
--- /dev/null
+++ b/tools/telemetry/telemetry/core/chrome/inspector_network.py
@@ -0,0 +1,17 @@
+# Copyright (c) 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+class InspectorNetwork(object):
+  def __init__(self, inspector_backend):
+    self._inspector_backend = inspector_backend
+
+  def ClearCache(self, timeout=60):
+    """Clears the browser's disk and memory cache."""
+    res = self._inspector_backend.SyncRequest({
+        'method': 'Network.canClearBrowserCache'
+        }, timeout)
+    assert res['result'], 'Cache clearing is not supported by this browser'
+    self._inspector_backend.SyncRequest({
+        'method': 'Network.clearBrowserCache'
+        }, timeout)