Remove Compiler.mainApp and Compiler.mainFunction

pkg/compiler/tool/perf.dart

Index: pkg/compiler/tool/perf.dart
diff --git a/pkg/compiler/tool/perf.dart b/pkg/compiler/tool/perf.dart
index 44d4f369065124aaf90b6d3d2bc61fee01811216..bea1371967d7abc1c4cf4ae48f8066a56903410e 100644
--- a/pkg/compiler/tool/perf.dart
+++ b/pkg/compiler/tool/perf.dart
@@ -344,10 +344,11 @@ class MyCompiler extends CompilerImpl {
       selfTask.measureSubtask('KernelCompiler.compileLoadedLibraries', () {
         ResolutionEnqueuer resolutionEnqueuer = startResolution();
         WorldImpactBuilderImpl mainImpact = new WorldImpactBuilderImpl();
-        mainFunction = frontendStrategy.computeMain(rootLibrary, mainImpact);
-        mirrorUsageAnalyzerTask.analyzeUsage(mainApp);
+        var mainFunction =
+            frontendStrategy.computeMain(rootLibrary, mainImpact);
+        mirrorUsageAnalyzerTask.analyzeUsage(rootLibrary);
 
-        deferredLoadTask.beforeResolution(this);
+        deferredLoadTask.beforeResolution(rootLibrary);
         impactStrategy = backend.createImpactStrategy(
             supportDeferredLoad: deferredLoadTask.isProgramSplit,
             supportDumpInfo: options.dumpInfo,
@@ -379,7 +380,7 @@ class MyCompiler extends CompilerImpl {
         }
 
         backend.onResolutionEnd();
-        closeResolution();
+        closeResolution(mainFunction);
         var program = (backend as dynamic).kernelTask.program;
         print('total libraries: ${program.libraries.length}');
       });