dart2js: Refactoring, documentation, and a few bugfixes in Namer class.

pkg/compiler/lib/src/js_backend/backend.dart

Index: pkg/compiler/lib/src/js_backend/backend.dart
diff --git a/pkg/compiler/lib/src/js_backend/backend.dart b/pkg/compiler/lib/src/js_backend/backend.dart
index 975581c922c175e6a839671ef8e12ffb6c41e3e3..204a733ee6f84cb77ef13bb9d4cd5ae704a70c83 100644
--- a/pkg/compiler/lib/src/js_backend/backend.dart
+++ b/pkg/compiler/lib/src/js_backend/backend.dart
@@ -539,7 +539,7 @@ class JavaScriptBackend extends Backend {
 
   String registerOneShotInterceptor(Selector selector) {
     Set<ClassElement> classes = getInterceptedClassesOn(selector.name);
-    String name = namer.getOneShotInterceptorName(selector, classes);
+    String name = namer.nameForOneShotInterceptor(selector, classes);

[floitsch, 2015/02/04 00:10:11]

This is not really accurate.
The `getOneShotInterceptor` function returns the one-shot interceptor. This is
the name for the `getOneShotInterceptor` function.
Should be nameForGetOneShotInterceptor

[asgerf, 2015/02/06 12:15:17]

Done.

     if (!oneShotInterceptors.containsKey(name)) {
       registerSpecializedGetInterceptor(classes);
       oneShotInterceptors[name] = selector;
@@ -738,7 +738,7 @@ class JavaScriptBackend extends Backend {
   }
 
   void registerSpecializedGetInterceptor(Set<ClassElement> classes) {
-    String name = namer.getInterceptorName(getInterceptorMethod, classes);
+    String name = namer.nameForGetInterceptor(classes);
     if (classes.contains(jsInterceptorClass)) {
       // We can't use a specialized [getInterceptorMethod], so we make
       // sure we emit the one with all checks.