More polish in prep for CrOS support

tools/chrome_remote_control/chrome_remote_control/tab_console.py

Index: tools/chrome_remote_control/chrome_remote_control/tab_console.py
diff --git a/tools/chrome_remote_control/chrome_remote_control/tab_console.py b/tools/chrome_remote_control/chrome_remote_control/tab_console.py
new file mode 100644
index 0000000000000000000000000000000000000000..b2d91beb4b695309b017254b022e0421488053a5
--- /dev/null
+++ b/tools/chrome_remote_control/chrome_remote_control/tab_console.py
@@ -0,0 +1,61 @@
+# Copyright (c) 2012 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.
+import json
+import logging
+
+import inspector_backend
+import util
+
+class TabConsole(object):
+  def __init__(self, inspector_backend):
+    self._inspector_backend = inspector_backend
+    self._inspector_backend.RegisterDomain(
+        'Console',
+        self._OnNotification,
+        self._OnClose)
+    self._message_output_stream = None
+    self._last_message = None
+    self._console_enabled = False
+
+  def _OnNotification(self, msg):
+    logging.debug("Notification: %s", json.dumps(msg, indent=2))
+    if msg["method"] == "Console.messageAdded":
+      self._last_message = "At %s:%i: %s" % (
+        msg["params"]["message"]["url"],
+        msg["params"]["message"]["line"],
+        msg["params"]["message"]["text"])
+      if self._message_output_stream:
+        self._message_output_stream.write(
+          "%s\n" % self._last_message)
+
+    elif msg["method"] == "Console.messageRepeatCountUpdated":
+      if self._message_output_stream:
+        self._message_output_stream.write(
+          "%s\n" % self._last_message)
+
+  def _OnClose(self):
+    pass
+
+  @property
+  def MessageOutputStream(self):
+    return self._message_output_stream
+
+  @MessageOutputStream.setter
+  def MessageOutputStream(self, stream):
+    self._message_output_stream = stream
+    self._UpdateConsoleEnabledState()
+
+  def _UpdateConsoleEnabledState(self):
+    enabled = self._message_output_stream != None
+    if enabled == self._console_enabled:
+      return
+
+    if enabled:
+      method_name = "enable"
+    else:
+      method_name = "disable"
+    self._inspector_backend.SyncRequest({
+        "method": "Console.%s" % method_name
+        })
+    self.enabled = enabled