Remove Compiler.mainApp and Compiler.mainFunction

pkg/compiler/lib/src/compiler.dart

Index: pkg/compiler/lib/src/compiler.dart
diff --git a/pkg/compiler/lib/src/compiler.dart b/pkg/compiler/lib/src/compiler.dart
index b591b4042bd5aa8550d3c77d7260fa1742475abc..8b587156fcf8cb18ef901e64a8b93f9714db9561 100644
--- a/pkg/compiler/lib/src/compiler.dart
+++ b/pkg/compiler/lib/src/compiler.dart
@@ -115,8 +115,7 @@ abstract class Compiler {
 
   ResolvedUriTranslator get resolvedUriTranslator;
 
-  LibraryEntity mainApp;
-  FunctionEntity mainFunction;
+  Uri mainLibraryUri;
 
   DiagnosticReporter get reporter => _reporter;
   Resolution get resolution => _resolution;
@@ -433,6 +432,7 @@ abstract class Compiler {
   Uri resolvePatchUri(String dartLibraryPath);
 
   Future runInternal(Uri uri) async {
+    mainLibraryUri = uri;
     // TODO(ahe): This prevents memory leaks when invoking the compiler
     // multiple times. Implement a better mechanism where we can store
     // such caches in the compiler and get access to them through a
@@ -457,6 +457,7 @@ abstract class Compiler {
         processLoadedLibraries(loadedLibraries);
       });
     }
+    LibraryEntity mainApp;
     if (uri != null) {
       if (options.analyzeOnly) {
         reporter.log('Analyzing $uri (${options.buildId})');
@@ -515,7 +516,8 @@ abstract class Compiler {
       selfTask.measureSubtask("Compiler.compileLoadedLibraries", () {
         ResolutionEnqueuer resolutionEnqueuer = startResolution();
         WorldImpactBuilderImpl mainImpact = new WorldImpactBuilderImpl();
-        mainFunction = frontendStrategy.computeMain(rootLibrary, mainImpact);
+        FunctionEntity mainFunction =
+            frontendStrategy.computeMain(rootLibrary, mainImpact);
 
         if (!options.loadFromDill) {
           // TODO(johnniwinther): Support mirrors usages analysis from dill.
@@ -526,7 +528,7 @@ abstract class Compiler {
         // compile-time constants that are metadata.  This means adding
         // something to the resolution queue.  So we cannot wait with
         // this until after the resolution queue is processed.
-        deferredLoadTask.beforeResolution(this);
+        deferredLoadTask.beforeResolution(rootLibrary);
         impactStrategy = backend.createImpactStrategy(
             supportDeferredLoad: deferredLoadTask.isProgramSplit,
             supportDumpInfo: options.dumpInfo,
@@ -596,8 +598,9 @@ abstract class Compiler {
         if (options.analyzeOnly) return;
         assert(mainFunction != null);
 
-        ClosedWorldRefiner closedWorldRefiner = closeResolution();
+        ClosedWorldRefiner closedWorldRefiner = closeResolution(mainFunction);
         ClosedWorld closedWorld = closedWorldRefiner.closedWorld;
+        mainFunction = closedWorld.elementEnvironment.mainFunction;
 
         reporter.log('Inferring types...');
         globalInference.runGlobalTypeInference(
@@ -637,7 +640,7 @@ abstract class Compiler {
       });
 
   /// Perform the steps needed to fully end the resolution phase.
-  ClosedWorldRefiner closeResolution() {
+  ClosedWorldRefiner closeResolution(FunctionEntity mainFunction) {
     phase = PHASE_DONE_RESOLVING;
 
     ClosedWorld closedWorld = resolutionWorldBuilder.closeWorld();
@@ -910,8 +913,8 @@ abstract class Compiler {
   Iterable<CodeLocation> computeUserCodeLocations(
       {bool assumeInUserCode: false}) {
     List<CodeLocation> userCodeLocations = <CodeLocation>[];
-    if (mainApp != null) {
-      userCodeLocations.add(new CodeLocation(mainApp.canonicalUri));
+    if (mainLibraryUri != null) {
+      userCodeLocations.add(new CodeLocation(mainLibraryUri));
     }
     if (librariesToAnalyzeWhenRun != null) {
       userCodeLocations.addAll(
@@ -955,7 +958,7 @@ abstract class Compiler {
         // Record as global error.
         // TODO(zarah): Extend element model to represent compile-time
         // errors instead of using a map.
-        element = mainFunction;
+        element = frontendStrategy.elementEnvironment.mainFunction;
       }
       elementsWithCompileTimeErrors
           .putIfAbsent(element, () => <DiagnosticMessage>[])