Additional fixes for external callback logging in profiler.

src/profiler/sampler.h

Index: src/profiler/sampler.h
diff --git a/src/profiler/sampler.h b/src/profiler/sampler.h
index d890f71c258aa5c8b70a970aa0de74aa70e752b2..8e8ef1cfc3e99dda279d165b8905223d5d189a65 100644
--- a/src/profiler/sampler.h
+++ b/src/profiler/sampler.h
@@ -34,7 +34,7 @@ struct TickSample {
   TickSample()
       : state(OTHER),
         pc(NULL),
-        external_callback(NULL),
+        external_callback_entry(NULL),
         frames_count(0),
         has_external_callback(false),
         update_stats(true),
@@ -49,7 +49,7 @@ struct TickSample {
   Address pc;      // Instruction pointer.
   union {
     Address tos;   // Top stack value (*sp).
-    Address external_callback;
+    Address external_callback_entry;
   };
   static const unsigned kMaxFramesCountLog2 = 8;
   static const unsigned kMaxFramesCount = (1 << kMaxFramesCountLog2) - 1;