Fix various TaskManager bugs and add new enhancements

chrome/browser/task_management/task_manager_interface.h

Index: chrome/browser/task_management/task_manager_interface.h
diff --git a/chrome/browser/task_management/task_manager_interface.h b/chrome/browser/task_management/task_manager_interface.h
index a58b7e72ff988e23f9c4465410ce9dd72f7fb753..9197785f5db9173224b0846f41fb74c293b94ca0 100644
--- a/chrome/browser/task_management/task_manager_interface.h
+++ b/chrome/browser/task_management/task_manager_interface.h
@@ -66,8 +66,9 @@ class TaskManagerInterface {
   // refresh cycle. A value of -1 means no valid value is currently available.
   virtual int GetIdleWakeupsPerSecond(TaskId task_id) const = 0;
 
-  // Returns the NaCl GDB debug stub port. A value of -1 means no valid value is
-  // currently available.
+  // Returns the NaCl GDB debug stub port. A value of
+  // |nacl::kGdbDebugStubPortUnknown| means no valid value is currently
+  // available. A value of -2 means NaCl is not enabled for this build.
   virtual int GetNaClDebugStubPort(TaskId task_id) const = 0;
 
   // On Windows, gets the current and peak number of GDI and USER handles in
@@ -104,6 +105,13 @@ class TaskManagerInterface {
   // usage.
   virtual int64 GetNetworkUsage(TaskId task_id) const = 0;
 
+  // Returns the total network usage (in bytes per second) during the current
+  // refresh cycle for the process on which the task with |task_id| is running.
+  // This is the sum of all the network usage of the individual tasks (that
+  // can be gotten by the above GetNetworkUsage()). A value of -1 means network
+  // usage calculation refresh is currently not available.
+  virtual int64 GetProcessTotalNetworkUsage(TaskId task_id) const = 0;
+
   // Returns the Sqlite used memory (in bytes) for the task with |task_id|.
   // A value of -1 means no valid value is currently available.
   virtual int64 GetSqliteMemoryUsed(TaskId task_id) const = 0;