dart2js: Use frequency of occurence to sort metadata indices.

pkg/js_ast/lib/src/printer.dart

Index: pkg/js_ast/lib/src/printer.dart
diff --git a/pkg/js_ast/lib/src/printer.dart b/pkg/js_ast/lib/src/printer.dart
index 57b35cfae4ce9cf8ae1e9175ffbac7165d61a1f1..e2df74393d4b17319893b3d8864f99840df24990 100644
--- a/pkg/js_ast/lib/src/printer.dart
+++ b/pkg/js_ast/lib/src/printer.dart
@@ -952,7 +952,28 @@ class Printer implements NodeVisitor {
   }
 
   @override
-  void visitLiteralBool(LiteralBool node) {
+  visitTokenExpression(TokenExpression node) {
+    // Continue printing with the expression value.
+    node.value.accept(this);

[sra1, 2015/05/27 19:38:51]

Either the precedence needs to be fixed or this code needs to account for
'incorrect' precedence.

[herhut, 2015/06/09 11:10:00]

Done.

+  }
+
+  @override
+  visitTokenNumber(TokenNumber node) {
+    String value = "${node.value}";
+    int charCode = value.codeUnitAt(0);
+    if (charCode == charCodes.$MINUS && lastCharCode == charCodes.$MINUS) {
+      out(" ");

[sra1, 2015/05/27 20:30:15]

I'd like to see a test that covers this case.

[herhut, 2015/06/09 11:10:00]

I have factored out the logic from visitLiteralNumber (where this came from)
into a shared helper. So the actual code will be tested by the tests for
LiteralNumber and no special test for the deferred version is needed.

+    }
+    out(value);
+  }
+
+  @override
+  visitTokenString(TokenString node) {
+    out(node.value);
+  }
+
+  @override
+  visitLiteralBool(LiteralBool node) {
     out(node.value ? "true" : "false");
   }
 
@@ -962,7 +983,12 @@ class Printer implements NodeVisitor {
   }
 
   @override
-  void visitLiteralNumber(LiteralNumber node) {
+  visitStringConcatenation(StringConcatenation node) {
+    node.visitChildren(this);
+  }
+
+  @override
+  visitLiteralNumber(LiteralNumber node) {
     int charCode = node.value.codeUnitAt(0);
     if (charCode == charCodes.$MINUS && lastCharCode == charCodes.$MINUS) {
       out(" ", isWhitespace: true);
@@ -1013,7 +1039,6 @@ class Printer implements NodeVisitor {
     out("{");
     indentMore();
     for (int i = 0; i < properties.length; i++) {
-      Expression value = properties[i].value;
       if (i != 0) {
         out(",");
         if (node.isOneLiner) spaceOut();