Only compute canonical names and clean new libraries

analysis-server-cold-analysis reduced from
~70 seconds to ~46 seconds.

Change-Id: I6e793f292beceda32817675625df90cd003bc19c
Reviewed-on: https://dart-review.googlesource.com/70264
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Kevin Millikin <kmillikin@google.com>

pkg/analyzer/lib/src/dart/analysis/frontend_resolution.dart

@@ -245,9 +245,13 @@ class FrontEndCompiler {
           }
         });
 
-        // TODO(scheglov) Only for new libraries?
-        _component.computeCanonicalNames();
-        _component.accept(new _ShadowCleaner());
+        _ShadowCleaner cleaner = new _ShadowCleaner();
+        for (var library in _component.libraries) {
+          if (!_results.containsKey(library.importUri)) {
+            _component.computeCanonicalNamesForLibrary(library);
+            library.accept(cleaner);
+          }
+        }
 
         _logger.run('Compute dependencies', _computeDependencies);
 

pkg/kernel/lib/ast.dart

@@ -5353,11 +5353,15 @@ class Component extends TreeNode {
 
   void computeCanonicalNames() {
     for (var library in libraries) {
-      root.getChildFromUri(library.importUri).bindTo(library.reference);
-      library.computeCanonicalNames();
+      computeCanonicalNamesForLibrary(library);
     }
   }
 
+  void computeCanonicalNamesForLibrary(Library library) {
+    root.getChildFromUri(library.importUri).bindTo(library.reference);
+    library.computeCanonicalNames();
+  }
+
   void unbindCanonicalNames() {
     root.unbindAll();
   }