Fix for interpolation codegen bug

sdk/lib/_internal/compiler/implementation/ssa/nodes.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/nodes.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ssa/nodes.dart b/sdk/lib/_internal/compiler/implementation/ssa/nodes.dart
index ea74d969dcd0434bc89d1a0c2f3093ef4f74facd..e037bcdbf0065e2959ba6d787a971ba0e7dff6a3 100644
--- a/sdk/lib/_internal/compiler/implementation/ssa/nodes.dart
+++ b/sdk/lib/_internal/compiler/implementation/ssa/nodes.dart
@@ -968,6 +968,11 @@ abstract class HInstruction implements Spannable {
   }
 
   bool isString(Compiler compiler) {

[sra1, 2014/02/19 03:06:22]

isString now matches the other isXXX methods with respect to nullability, rather
than being opposite.

+    return instructionType.containsOnlyString(compiler)
+        && !instructionType.isNullable;
+  }
+
+  bool isStringOrNull(Compiler compiler) {
     return instructionType.containsOnlyString(compiler);
   }