AllocationProfiler: Inital version of RecordObjectAllocation for hydrogen.

src/x64/lithium-x64.cc

Index: src/x64/lithium-x64.cc
diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index 93a2eb7fcc3ff52c16d1fddddaabdb1e0b8be9e8..d7c9a6a4310eadd104e74852a39f1a4998a6b30a 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -2385,6 +2385,11 @@ LInstruction* LChunkBuilder::DoCallStub(HCallStub* instr) {
 }
 
 
+LInstruction* LChunkBuilder::DoCallExternal(HCallExternal* instr) {
+  return MarkAsCall(new(zone()) LCallExternal(), instr);
+}
+
+
 LInstruction* LChunkBuilder::DoArgumentsObject(HArgumentsObject* instr) {
   // There are no real uses of the arguments object.
   // arguments.length and element access are supported directly on