Revert of Also skip when the target is the global object (patchset #1 id:1 of...

Revert of Also skip when the target is the global object (patchset #1 id:1 of https://codereview.chromium.org/961723002/)

Reason for revert:
Breaks unscopables and fix attempt needed to be reverted too.

Original issue's description:
> Also skip when the target is the global object
>
> BUG=
>
> Committed: https://crrev.com/cc918d30b9d586ce974b71232473f2ae3c5e7847
> Cr-Commit-Position: refs/heads/master@{#26887}

TBR=jkummerow@chromium.org,verwaest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/960363002

Cr-Commit-Position: refs/heads/master@{#26900}

src/ic/arm/handler-compiler-arm.cc

@@ -498,8 +498,7 @@ Register PropertyHandlerCompiler::CheckPrototypes(
   // Log the check depth.
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
 
-  if (!current_map->IsJSGlobalObjectMap() &&
-      (depth != 0 || check == CHECK_ALL_MAPS)) {
+  if (depth != 0 || check == CHECK_ALL_MAPS) {
     // Check the holder map.
     __ ldr(scratch1, FieldMemOperand(reg, HeapObject::kMapOffset));
     Handle<WeakCell> cell = Map::WeakCellForMap(current_map);

src/ic/arm64/handler-compiler-arm64.cc

@@ -548,8 +548,7 @@ Register PropertyHandlerCompiler::CheckPrototypes(
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
 
   // Check the holder map.
-  if (!current_map->IsJSGlobalObjectMap() &&
-      (depth != 0 || check == CHECK_ALL_MAPS)) {
+  if (depth != 0 || check == CHECK_ALL_MAPS) {
     // Check the holder map.
     __ Ldr(scratch1, FieldMemOperand(reg, HeapObject::kMapOffset));
     Handle<WeakCell> cell = Map::WeakCellForMap(current_map);

src/ic/ia32/handler-compiler-ia32.cc

@@ -499,8 +499,7 @@ Register PropertyHandlerCompiler::CheckPrototypes(
   // Log the check depth.
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
 
-  if (!current_map->IsJSGlobalObjectMap() &&
-      (depth != 0 || check == CHECK_ALL_MAPS)) {
+  if (depth != 0 || check == CHECK_ALL_MAPS) {
     // Check the holder map.
     __ mov(scratch1, FieldOperand(reg, HeapObject::kMapOffset));
     Handle<WeakCell> cell = Map::WeakCellForMap(current_map);

src/ic/x64/handler-compiler-x64.cc

@@ -501,8 +501,7 @@ Register PropertyHandlerCompiler::CheckPrototypes(
   // Log the check depth.
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
 
-  if (!current_map->IsJSGlobalObjectMap() &&
-      (depth != 0 || check == CHECK_ALL_MAPS)) {
+  if (depth != 0 || check == CHECK_ALL_MAPS) {
     __ movp(scratch1, FieldOperand(reg, HeapObject::kMapOffset));
     Handle<WeakCell> cell = Map::WeakCellForMap(current_map);
     __ CmpWeakValue(scratch1, cell, scratch2);