[Interpereter] Avoid Canonicalizing Handles created during bytecode finalization

Should fix a performance regression introduced by introducing
a CanonicalHandleScope for bytecode compilation. Also fix a
missing CanonicalHandleScope in GetSharedFunctionInfo.

BUG=chromium:634953

Review-Url: https://codereview.chromium.org/2226923002
Cr-Commit-Position: refs/heads/master@{#38583}

src/compiler.cc

@@ -1809,6 +1809,13 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfo(
   RuntimeCallTimerScope runtimeTimer(isolate, &RuntimeCallStats::CompileCode);
   TRACE_EVENT_RUNTIME_CALL_STATS_TRACING_SCOPED(
       isolate, &tracing::TraceEventStatsTable::CompileCode);
+
+  // Create a canonical handle scope if compiling ignition bytecode. This is
+  // required by the constant array builder to de-duplicate common objects
+  // without dereferencing handles.
+  std::unique_ptr<CanonicalHandleScope> canonical;
+  if (FLAG_ignition) canonical.reset(new CanonicalHandleScope(info.isolate()));
+
   if (lazy) {
     info.SetCode(isolate->builtins()->CompileLazy());
   } else if (Renumber(info.parse_info()) && GenerateUnoptimizedCode(&info)) {

src/interpreter/bytecode-generator.cc

@@ -627,12 +627,16 @@ BytecodeGenerator::BytecodeGenerator(CompilationInfo* info)
 }
 
 Handle<BytecodeArray> BytecodeGenerator::MakeBytecode() {
+  // Create an inner HandleScope to avoid unnecessarily canonicalizing handles
+  // created as part of bytecode finalization.
+  HandleScope scope(isolate());
+
   GenerateBytecode();
   FinalizeBytecode();
 
   if (HasStackOverflow()) return Handle<BytecodeArray>();
 
-  return builder()->ToBytecodeArray();
+  return scope.CloseAndEscape(builder()->ToBytecodeArray());
 }
 
 void BytecodeGenerator::FinalizeBytecode() {