Change default timestamp to 64 bits in all webrtc directories.

webrtc/base/logging.cc

Index: webrtc/base/logging.cc
diff --git a/webrtc/base/logging.cc b/webrtc/base/logging.cc
index 019a31623be1333f48383362ed9fe74c21619fb9..fbecb983a44e9acda5e5d7b3767ea6e8b368d08a 100644
--- a/webrtc/base/logging.cc
+++ b/webrtc/base/logging.cc
@@ -125,7 +125,7 @@ LogMessage::LogMessage(const char* file,
                        const char* module)
     : severity_(sev), tag_(kLibjingle) {
   if (timestamp_) {
-    uint32_t time = TimeSince(LogStartTime());
+    int64_t time = TimeSince(LogStartTime());
     // Also ensure WallClockStartTime is initialized, so that it matches
     // LogStartTime.
     WallClockStartTime();
@@ -212,8 +212,8 @@ LogMessage::~LogMessage() {
   }
 }
 
-uint32_t LogMessage::LogStartTime() {
-  static const uint32_t g_start = Time();
+int64_t LogMessage::LogStartTime() {
+  static const int64_t g_start = Time();
   return g_start;
 }