Implement a new flow event API that allows binding flow events and regular events.

ppapi/shared_impl/ppb_trace_event_impl.cc

Index: ppapi/shared_impl/ppb_trace_event_impl.cc
diff --git a/ppapi/shared_impl/ppb_trace_event_impl.cc b/ppapi/shared_impl/ppb_trace_event_impl.cc
index aabc4f255467f5da49147e8efa5efff077f4cbe8..eb0cd3dee27bbc76e4453cd71516c78c7b108c2a 100644
--- a/ppapi/shared_impl/ppb_trace_event_impl.cc
+++ b/ppapi/shared_impl/ppb_trace_event_impl.cc
@@ -78,19 +78,18 @@ void TraceEventImpl::AddTraceEventWithThreadIdAndTimestamp(
           static_cast<const unsigned char*>(category_enabled),
           name,
           id,
-          trace_event_internal::kNoId,
           thread_id,

[dsinclair, 2015/07/21 18:11:49]

This file shouldn't need to change yet right? We added the overloads for this
reason.

[yuhaoz, 2015/07/21 18:22:34]

Right that's why I removed the kNoId. fmeawad@ for context_id. I removed it so
that it uses the overloaded version.
 

[dsinclair, 2015/07/21 18:32:50]

Just add the context_id into the overloaded version. We do want to move off the
old API onto the new one, I just think they should be separate CLs. So, this CL
shouldn't change Angle or PPAPI and we update each of them later then remove the
old API.

           base::TraceTicks::FromInternalValue(timestamp),
           num_args,
           arg_names,
           arg_types,
-      // This cast is necessary for LP64 systems, where uint64_t is defined as
-      // an unsigned long int, but trace_event internals are hermetic and
-      // accepts an |unsigned long long*|.  The pointer types are compatible but
-      // the compiler throws an error without an explicit cast.
-      reinterpret_cast<const unsigned long long*>(arg_values),
-      NULL,
-      flags);
+          // This cast is necessary for LP64 systems, where uint64_t is defined as

[vmpstr, 2015/07/21 18:03:41]

You'll probably need to rewrap the comment to be 80-col

+          // an unsigned long int, but trace_event internals are hermetic and
+          // accepts an |unsigned long long*|.  The pointer types are compatible but
+          // the compiler throws an error without an explicit cast.
+          reinterpret_cast<const unsigned long long*>(arg_values),
+          NULL,
+          flags);
 }
 
 // static