Add missing if (FLAG_verify_heap) checks around heap verification

BUG=chromium:449943
R=svenpanne@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/848403003

Cr-Commit-Position: refs/heads/master@{#26127}

src/api.cc

@@ -409,7 +409,9 @@ i::Object** V8::GlobalizeReference(i::Isolate* isolate, i::Object** obj) {
   LOG_API(isolate, "Persistent::New");
   i::Handle<i::Object> result = isolate->global_handles()->Create(*obj);
 #ifdef VERIFY_HEAP
-  (*obj)->ObjectVerify();
+  if (i::FLAG_verify_heap) {
+    (*obj)->ObjectVerify();
+  }
 #endif  // VERIFY_HEAP
   return result.location();
 }
@@ -418,7 +420,9 @@ i::Object** V8::GlobalizeReference(i::Isolate* isolate, i::Object** obj) {
 i::Object** V8::CopyPersistent(i::Object** obj) {
   i::Handle<i::Object> result = i::GlobalHandles::CopyGlobal(obj);
 #ifdef VERIFY_HEAP
-  (*obj)->ObjectVerify();
+  if (i::FLAG_verify_heap) {
+    (*obj)->ObjectVerify();
+  }
 #endif  // VERIFY_HEAP
   return result.location();
 }

src/bootstrapper.cc

@@ -2164,7 +2164,9 @@ bool Genesis::InstallNatives() {
   }
 
 #ifdef VERIFY_HEAP
-  builtins->ObjectVerify();
+  if (FLAG_verify_heap) {
+    builtins->ObjectVerify();
+  }
 #endif
 
   return true;

src/execution.cc

@@ -109,7 +109,9 @@ MUST_USE_RESULT static MaybeHandle<Object> Invoke(
   }
 
 #ifdef VERIFY_HEAP
-  value->ObjectVerify();
+  if (FLAG_verify_heap) {
+    value->ObjectVerify();
+  }
 #endif
 
   // Update the pending exception flag and return the value.

src/heap-snapshot-generator.cc

@@ -2551,13 +2551,17 @@ bool HeapSnapshotGenerator::GenerateSnapshot() {
 
 #ifdef VERIFY_HEAP
   Heap* debug_heap = heap_;
-  debug_heap->Verify();
+  if (FLAG_verify_heap) {
+    debug_heap->Verify();
+  }
 #endif
 
   SetProgressTotal(2);  // 2 passes.
 
 #ifdef VERIFY_HEAP
-  debug_heap->Verify();
+  if (FLAG_verify_heap) {
+    debug_heap->Verify();
+  }
 #endif
 
   snapshot_->AddSyntheticRootEntries();