Bug fix - use type of input, not type of result, for throw-on-null check

pkg/compiler/lib/src/ssa/nodes.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import '../closure.dart';
 import '../common.dart';
 import '../compiler.dart' show Compiler;
 import '../constants/constant_system.dart';
 import '../constants/values.dart';
 import '../dart_types.dart';
@@ skipping 1895 matching lines @@
   HForeignCode.statement(js.Template codeTemplate, List<HInstruction> inputs,
       SideEffects effects, native.NativeBehavior nativeBehavior, TypeMask type)
       : this(codeTemplate, type, inputs,
             isStatement: true,
             effects: effects,
             nativeBehavior: nativeBehavior);
 
   accept(HVisitor visitor) => visitor.visitForeignCode(this);
 
   bool isJsStatement() => isStatement;
-  bool canThrow() =>
-      canBeNull() ? throwBehavior.canThrow : throwBehavior.onNonNull.canThrow;
+  bool canThrow() {
+    if (inputs.length > 0) {
+      return inputs.first.canBeNull()
+          ? throwBehavior.canThrow
+          : throwBehavior.onNonNull.canThrow;
+    }
+    return throwBehavior.canThrow;
+  }
 
   bool onlyThrowsNSM() => throwBehavior.isOnlyNullNSMGuard;
 
   bool get isAllocation =>
       nativeBehavior != null && nativeBehavior.isAllocation && !canBeNull();
 
   String toString() => 'HForeignCode("${codeTemplate.source}",$inputs)';
 }
 
 abstract class HInvokeBinary extends HInstruction {
@@ skipping 1520 matching lines @@
 class HDynamicType extends HRuntimeType {
   HDynamicType(DynamicType dartType, TypeMask instructionType)
       : super(const <HInstruction>[], dartType, instructionType);
 
   accept(HVisitor visitor) => visitor.visitDynamicType(this);
 
   int typeCode() => HInstruction.DYNAMIC_TYPE_TYPECODE;
 
   bool typeEquals(HInstruction other) => other is HDynamicType;
 }