Change default timestamp to 64 bits in all webrtc directories.

webrtc/base/sharedexclusivelock_unittest.cc

Index: webrtc/base/sharedexclusivelock_unittest.cc
diff --git a/webrtc/base/sharedexclusivelock_unittest.cc b/webrtc/base/sharedexclusivelock_unittest.cc
index 9b64ed760afa89b2551d47355a46cc0e8299cac1..0d7f28be08a52d967ab0aac5a29111fc3d33cf71 100644
--- a/webrtc/base/sharedexclusivelock_unittest.cc
+++ b/webrtc/base/sharedexclusivelock_unittest.cc
@@ -39,12 +39,12 @@ class SharedExclusiveTask : public MessageHandler {
     worker_thread_->Start();
   }
 
-  int waiting_time_in_ms() const { return waiting_time_in_ms_; }
+  int64_t waiting_time_in_ms() const { return waiting_time_in_ms_; }
 
  protected:
   scoped_ptr<Thread> worker_thread_;
   SharedExclusiveLock* shared_exclusive_lock_;
-  int waiting_time_in_ms_;
+  int64_t waiting_time_in_ms_;
   int* value_;
   bool* done_;
 };
@@ -68,7 +68,7 @@ class ReadTask : public SharedExclusiveTask {
     TypedMessageData<int*>* message_data =
         static_cast<TypedMessageData<int*>*>(message->pdata);
 
-    uint32_t start_time = Time();
+    int64_t start_time = Time();
     {
       SharedScope ss(shared_exclusive_lock_);
       waiting_time_in_ms_ = TimeDiff(Time(), start_time);