Revert 193811 "Move browser and url to WebContents from Tab."

Reverting because url uses BrowserBackend.tab_list_backend, which is not correct for WebContents.

> Move browser and url to WebContents from Tab.
> 
> BUG=None
> TEST=unit tests
> NOTRY=true
> 
> Review URL: https://chromiumcodereview.appspot.com/14185002

Review URL: https://codereview.chromium.org/14064014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@194978 0039d316-1c4b-4281-b951-d872f2087c98

tools/telemetry/telemetry/core/tab.py

@@ -22,6 +22,15 @@ class Tab(web_contents.WebContents):
   def __del__(self):
     super(Tab, self).__del__()
 
+  @property
+  def browser(self):
+    """The browser in which this tab resides."""
+    return self._inspector_backend.browser
+
+  @property
+  def url(self):
+    return self._inspector_backend.url
+
   @property
   def dom_stats(self):
     """A dictionary populated with measured DOM statistics.

tools/telemetry/telemetry/core/web_contents.py

@@ -24,15 +24,6 @@ class WebContents(object):
     Be sure to check browser.supports_tab_control."""
     self._inspector_backend.Close()
 
-  @property
-  def browser(self):
-    """The browser in which this WebContents resides."""
-    return self._inspector_backend.browser
-
-  @property
-  def url(self):
-    return self._inspector_backend.url
-
   def WaitForDocumentReadyStateToBeComplete(self,
       timeout=DEFAULT_WEB_CONTENTS_TIMEOUT):
     self._inspector_backend.WaitForDocumentReadyStateToBeComplete(timeout)