Put back the unit test on optimizing removeLast to pop. Also don't forget that jsArrayRemoveLast mi…

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

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of ssa;
 
 class SsaCodeGeneratorTask extends CompilerTask {
 
   final JavaScriptBackend backend;
 
@@ skipping 1528 matching lines @@
   }
 
   visitInvokeDynamicMethod(HInvokeDynamicMethod node) {
     use(node.receiver);
     js.Expression object = pop();
     SourceString name = node.selector.name;
     String methodName;
     List<js.Expression> arguments = visitArguments(node.inputs);
     Element target = node.element;
 
-    // Avoid adding the generative constructor name to the list of
-    // seen selectors.
-    if (target != null && target.isGenerativeConstructorBody()) {
-      methodName = name.slowToString();
-    } else if (target == backend.jsArrayAdd) {
-      methodName = 'push';
-    } else if (target == backend.jsArrayRemoveLast) {
-      methodName = 'pop';
-    } else if (target == backend.jsStringSplit) {
-      methodName = 'split';
-      // Split returns a List, so we make sure the backend knows the
-      // list class is instantiated.
-      world.registerInstantiatedClass(compiler.listClass);
-    } else if (target == backend.jsStringConcat) {
-      push(new js.Binary('+', object, arguments[0]), node);
-      return;
-    } else {
+    if (target != null) {
+      // Avoid adding the generative constructor name to the list of
+      // seen selectors.
+      if (target.isGenerativeConstructorBody()) {
+        methodName = name.slowToString();
+      } else if (target == backend.jsArrayAdd) {
+        methodName = 'push';
+      } else if (target == backend.jsArrayRemoveLast) {
+        methodName = 'pop';
+      } else if (target == backend.jsStringSplit) {
+        methodName = 'split';
+        // Split returns a List, so we make sure the backend knows the
+        // list class is instantiated.
+        world.registerInstantiatedClass(compiler.listClass);
+      } else if (target == backend.jsStringConcat) {
+        push(new js.Binary('+', object, arguments[0]), node);
+        return;
+      }
+    }
+
+    if (methodName == null) {
       methodName = backend.namer.instanceMethodInvocationName(
           node.selector.library, name, node.selector);
       bool inLoop = node.block.enclosingLoopHeader != null;
 
       Selector selector = getOptimizedSelectorFor(node, node.selector);
       if (node.isInterceptorCall) {
         backend.addInterceptedSelector(selector);
       }
       // Register this invocation to collect the types used at all call sites.
       backend.registerDynamicInvocation(node, selector, types);
@@ skipping 1454 matching lines @@
   if (leftType.canBeNull() && rightType.canBeNull()) {
     if (left.isConstantNull() || right.isConstantNull() ||
         (leftType.isPrimitive() && leftType == rightType)) {
       return '==';
     }
     return null;
   } else {
     return '===';
   }
 }