Revert of Change WebContents::last_active_time_ to Time instead of Timeticks.

components/devtools_discovery/devtools_target_descriptor.h

 // Copyright 2015 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.
 
 #ifndef COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_TARGET_DESCRIPTOR_H_
 #define COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_TARGET_DESCRIPTOR_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 32 matching lines @@
   // Returns the target description.
   virtual std::string GetDescription() const = 0;
 
   // Returns the url associated with this target.
   virtual GURL GetURL() const = 0;
 
   // Returns the favicon url for this target.
   virtual GURL GetFaviconURL() const = 0;
 
   // Returns the time when the target was last active.
-  virtual base::Time GetLastActiveTime() const = 0;
+  virtual base::TimeTicks GetLastActivityTime() const = 0;
 
   // Returns true if the debugger is attached to the target.
   virtual bool IsAttached() const = 0;
 
   // Returns the agent host for this target.
   virtual scoped_refptr<content::DevToolsAgentHost> GetAgentHost() const = 0;
 
   // Activates the target. Returns false if the operation failed.
   virtual bool Activate() const = 0;
 
   // Closes the target. Returns false if the operation failed.
   virtual bool Close() const = 0;
 };
 
 }  // namespace devtools_discovery
 
 #endif  // COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_TARGET_DESCRIPTOR_H_