Remove Compiler.mainApp and Compiler.mainFunction

tests/compiler/dart2js/no_such_method_enabled_test.dart

Index: tests/compiler/dart2js/no_such_method_enabled_test.dart
diff --git a/tests/compiler/dart2js/no_such_method_enabled_test.dart b/tests/compiler/dart2js/no_such_method_enabled_test.dart
index 286635d19cdec8a3b0720dc6758e84e321fa0b8b..4696efc97adb8f421717573d6b4d8c00db0bd0bf 100644
--- a/tests/compiler/dart2js/no_such_method_enabled_test.dart
+++ b/tests/compiler/dart2js/no_such_method_enabled_test.dart
@@ -279,8 +279,8 @@ checkTest(Compiler compiler, NoSuchMethodTest test, {bool testComplexReturns}) {
 
   // Test [NoSuchMethodResolver] results for each method.
   for (NoSuchMethodInfo info in test.methods) {
-    ClassEntity cls =
-        elementEnvironment.lookupClass(compiler.mainApp, info.className);
+    ClassEntity cls = elementEnvironment.lookupClass(
+        elementEnvironment.mainLibrary, info.className);
     Expect.isNotNull(cls, "Class ${info.className} not found.");
     FunctionEntity noSuchMethod =
         elementEnvironment.lookupClassMember(cls, 'noSuchMethod');
@@ -289,8 +289,8 @@ checkTest(Compiler compiler, NoSuchMethodTest test, {bool testComplexReturns}) {
     if (info.superClassName == null) {
       Expect.equals(ObjectNSM, resolver.getSuperNoSuchMethod(noSuchMethod));
     } else {
-      ClassEntity superclass =
-          elementEnvironment.lookupClass(compiler.mainApp, info.superClassName);
+      ClassEntity superclass = elementEnvironment.lookupClass(
+          elementEnvironment.mainLibrary, info.superClassName);
       Expect.isNotNull(
           superclass, "Superclass ${info.superClassName} not found.");
       FunctionEntity superNoSuchMethod =
@@ -317,8 +317,8 @@ checkTest(Compiler compiler, NoSuchMethodTest test, {bool testComplexReturns}) {
   // the [NoSuchMethodResolver] results which are therefore tested for all
   // methods first.
   for (NoSuchMethodInfo info in test.methods) {
-    ClassEntity cls =
-        elementEnvironment.lookupClass(compiler.mainApp, info.className);
+    ClassEntity cls = elementEnvironment.lookupClass(
+        elementEnvironment.mainLibrary, info.className);
     Expect.isNotNull(cls, "Class ${info.className} not found.");
     FunctionEntity noSuchMethod =
         elementEnvironment.lookupClassMember(cls, 'noSuchMethod');