Reland of "Remove ExternalArray, derived types, and element kinds"

src/arm64/lithium-arm64.cc

Index: src/arm64/lithium-arm64.cc
diff --git a/src/arm64/lithium-arm64.cc b/src/arm64/lithium-arm64.cc
index c432f245a539b4c976190961188bf05a271a680f..d5c7b4e38ad794ed670a96dce6b12b1b4230c995 100644
--- a/src/arm64/lithium-arm64.cc
+++ b/src/arm64/lithium-arm64.cc
@@ -1728,7 +1728,7 @@ LInstruction* LChunkBuilder::DoLoadKeyed(HLoadKeyed* instr) {
   LOperand* elements = UseRegister(instr->elements());
   LOperand* key = UseRegisterOrConstant(instr->key());
 
-  if (!instr->is_typed_elements()) {
+  if (!instr->is_fixed_typed_array()) {
     if (instr->representation().IsDouble()) {
       LOperand* temp = (!instr->key()->IsConstant() ||
                         instr->RequiresHoleCheck())
@@ -1762,8 +1762,7 @@ LInstruction* LChunkBuilder::DoLoadKeyed(HLoadKeyed* instr) {
     LOperand* temp = instr->key()->IsConstant() ? NULL : TempRegister();
     LInstruction* result = DefineAsRegister(
         new(zone()) LLoadKeyedExternal(elements, key, temp));
-    if ((elements_kind == EXTERNAL_UINT32_ELEMENTS ||
-         elements_kind == UINT32_ELEMENTS) &&
+    if (elements_kind == UINT32_ELEMENTS &&
         !instr->CheckFlag(HInstruction::kUint32)) {
       result = AssignEnvironment(result);
     }
@@ -2367,7 +2366,7 @@ LInstruction* LChunkBuilder::DoStoreKeyed(HStoreKeyed* instr) {
   LOperand* elements = NULL;
   LOperand* val = NULL;
 
-  if (!instr->is_typed_elements() &&
+  if (!instr->is_fixed_typed_array() &&
       instr->value()->representation().IsTagged() &&
       instr->NeedsWriteBarrier()) {
     // RecordWrite() will clobber all registers.
@@ -2380,7 +2379,7 @@ LInstruction* LChunkBuilder::DoStoreKeyed(HStoreKeyed* instr) {
     temp = instr->key()->IsConstant() ? NULL : TempRegister();
   }
 
-  if (instr->is_typed_elements()) {
+  if (instr->is_fixed_typed_array()) {
     DCHECK((instr->value()->representation().IsInteger32() &&
             !IsDoubleOrFloatElementsKind(instr->elements_kind())) ||
            (instr->value()->representation().IsDouble() &&