dart2js: patch file support cleanup

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

Index: pkg/compiler/lib/src/ssa/builder_kernel.dart
diff --git a/pkg/compiler/lib/src/ssa/builder_kernel.dart b/pkg/compiler/lib/src/ssa/builder_kernel.dart
index e9d03deed2f83414c9c4e723a87a5b58f8249b86..6e1c994162e72dd815019d53163c0417f2897d1a 100644
--- a/pkg/compiler/lib/src/ssa/builder_kernel.dart
+++ b/pkg/compiler/lib/src/ssa/builder_kernel.dart
@@ -2416,21 +2416,15 @@ class KernelSsaBuilder extends ir.Visitor with GraphBuilder {
       return;
     }
     String name = _foreignConstantStringArgument(invocation, 0, 'JS_GET_FLAG');
-    bool value = false;
-    switch (name) {
-      case 'MUST_RETAIN_METADATA':
-        value = mirrorsData.mustRetainMetadata;
-        break;
-      case 'USE_CONTENT_SECURITY_POLICY':
-        value = options.useContentSecurityPolicy;
-        break;
-      default:
-        reporter.reportErrorMessage(
-            astAdapter.getNode(invocation),
-            MessageKind.GENERIC,
-            {'text': 'Error: Unknown internal flag "$name".'});
-    }
-    stack.add(graph.addConstantBool(value, closedWorld));
+    bool value = getFlagValue(name);
+    if (value == null) {
+      reporter.reportErrorMessage(
+          astAdapter.getNode(invocation),
+          MessageKind.GENERIC,
+          {'text': 'Error: Unknown internal flag "$name".'});
+    } else {
+      stack.add(graph.addConstantBool(value, closedWorld));
+    }
   }
 
   void handleJsInterceptorConstant(ir.StaticInvocation invocation) {
@@ -2503,8 +2497,7 @@ class KernelSsaBuilder extends ir.Visitor with GraphBuilder {
     push(new HForeignCode(nativeBehavior.codeTemplate, ssaType, inputs,
         isStatement: !nativeBehavior.codeTemplate.isExpression,
         effects: nativeBehavior.sideEffects,
-        nativeBehavior: nativeBehavior)
-      ..sourceInformation = sourceInformation);
+        nativeBehavior: nativeBehavior)..sourceInformation = sourceInformation);
   }
 
   void handleJsStringConcat(ir.StaticInvocation invocation) {
@@ -2608,8 +2601,9 @@ class KernelSsaBuilder extends ir.Visitor with GraphBuilder {
     _pushDynamicInvocation(
         invocation,
         astAdapter.typeOfInvocation(invocation, closedWorld),
-        <HInstruction>[receiver]..addAll(
-            _visitArgumentsForDynamicTarget(selector, invocation.arguments)));
+        <HInstruction>[receiver]
+          ..addAll(
+              _visitArgumentsForDynamicTarget(selector, invocation.arguments)));
   }
 
   bool _handleEqualsNull(ir.MethodInvocation invocation) {