Sort the output (for now just the classes and instance members).

lib/compiler/implementation/scanner/token.dart

Index: lib/compiler/implementation/scanner/token.dart
diff --git a/lib/compiler/implementation/scanner/token.dart b/lib/compiler/implementation/scanner/token.dart
index ddd921b074745f311777c71ec04380a0e8b2f4a4..4405d76878d5fbacea9fad2881816721bf437540 100644
--- a/lib/compiler/implementation/scanner/token.dart
+++ b/lib/compiler/implementation/scanner/token.dart
@@ -126,7 +126,8 @@ class StringToken extends Token {
   String slowToString() => value.slowToString();
 }
 
-interface SourceString extends Hashable, Iterable<int> default StringWrapper {
+interface SourceString extends Comparable, Hashable, Iterable<int>
+    default StringWrapper {
   const SourceString(String string);
 
   void printOn(StringBuffer sb);
@@ -146,6 +147,20 @@ interface SourceString extends Hashable, Iterable<int> default StringWrapper {
   bool isPrivate();
 }
 
+int sourceStringCompare(SourceString string1, SourceString string2) {
+  Iterator<int> iterator1 = string1.iterator();
+  Iterator<int> iterator2 = string2.iterator();
+  while (iterator1.hasNext()) {
+    if (!iterator2.hasNext()) return 1;
+    int char1 = iterator1.next();
+    int char2 = iterator2.next();
+    int comparison = char1.compareTo(char2);
+    if (comparison != 0) return comparison;
+  }
+  if (iterator2.hasNext()) return -1;
+  return 0;
+}
+
 class StringWrapper implements SourceString {
   final String stringValue;
 
@@ -153,6 +168,14 @@ class StringWrapper implements SourceString {
 
   int hashCode() => stringValue.hashCode();
 
+  int compareTo(SourceString other) {
+    if (other is StringWrapper) {
+      StringWrapper otherWrapper = other;
+      return stringValue.compareTo(otherWrapper.stringValue);
+    }
+    return sourceStringCompare(this, other);
+  }
+
   bool operator ==(other) {
     return other is SourceString && toString() == other.slowToString();
   }