[Isolates] Cleanup of codepaths slowing down Dromaeo in browser.

src/log.h

Index: src/log.h
diff --git a/src/log.h b/src/log.h
index 0791fb9e4dbb30e44322fd3ea74580aa235fb195..00e27a7e1329bfa4c2ef3faaade962120d96ed92 100644
--- a/src/log.h
+++ b/src/log.h
@@ -79,14 +79,16 @@ class CompressionHelper;
 #undef LOG
 // TODO(isolates): pass isolate pointer here.
 #ifdef ENABLE_LOGGING_AND_PROFILING
-#define LOG(Call)                                   \
-  do {                                              \
-    v8::internal::Logger* logger =                  \
-        v8::internal::Isolate::Current()->logger(); \
-    if (logger->is_logging())                       \
-      logger->Call;                                 \
+#define LOG_FOR_ISOLATE(isolate, Call)                \
+  do {                                                \
+    v8::internal::Logger* logger = isolate->logger(); \
+    if (logger->is_logging())                         \
+      logger->Call;                                   \
   } while (false)
+
+#define LOG(Call) LOG_FOR_ISOLATE(v8::internal::Isolate::Current(), Call)
 #else
+#define LOG_FOR_ISOLATE(isolate, Call) ((void) 0)
 #define LOG(Call) ((void) 0)
 #endif