Make string juxtaposition combine properly with string interpolations.

frog/leg/ssa/codegen.dart

Index: frog/leg/ssa/codegen.dart
diff --git a/frog/leg/ssa/codegen.dart b/frog/leg/ssa/codegen.dart
index b2ba7656c1f4a0436d151207817e6cda5585dccd..bf34ae9e006151c8a5f49ef05ad0c543de660fb5 100644
--- a/frog/leg/ssa/codegen.dart
+++ b/frog/leg/ssa/codegen.dart
@@ -144,6 +144,7 @@ class SsaCodeGenerator implements HVisitor {
       buffer.add('(');
     }
   }
+
   void endExpression(int precedence) {
     if (precedence < expectedPrecedence) {
       buffer.add(')');
@@ -671,7 +672,7 @@ class SsaCodeGenerator implements HVisitor {
     } else {
       buffer.add(compiler.namer.CURRENT_ISOLATE);
       buffer.add(".");
-      buffer.add(name);      
+      buffer.add(name);
     }
   }