Add lookupInScope to DeclarationMirror.

sdk/lib/_internal/dartdoc/lib/dartdoc.dart

Index: sdk/lib/_internal/dartdoc/lib/dartdoc.dart
diff --git a/sdk/lib/_internal/dartdoc/lib/dartdoc.dart b/sdk/lib/_internal/dartdoc/lib/dartdoc.dart
index 02748759b184659a1ffdc0ffaff37190aeb9138c..21f5d5eea316f7e49f3e15e7f5246a70dd9c06bf 100644
--- a/sdk/lib/_internal/dartdoc/lib/dartdoc.dart
+++ b/sdk/lib/_internal/dartdoc/lib/dartdoc.dart
@@ -975,7 +975,6 @@ class Dartdoc {
     }
     _totalLibraries++;
     _currentLibrary = library;
-    _currentType = null;
 
     startFile(libraryUrl(library));
     writeHeader('${displayName(library)} Library',
@@ -1032,6 +1031,8 @@ class Dartdoc {
 
       docType(type);
     }
+
+    _currentLibrary = null;
   }
 
   void docTypes(List types, String header) {
@@ -1102,6 +1103,8 @@ class Dartdoc {
     writeTypeFooter();
     writeFooter();
     endFile();
+
+    _currentType = null;
   }
 
   /** Override this to write additional content at the end of a type's page. */
@@ -1575,6 +1578,8 @@ class Dartdoc {
     writeln('</div>');
 
     writeln('</div>');
+
+    _currentMember = null;
   }
 
   void docField(ContainerMirror host, VariableMirror field,
@@ -1660,6 +1665,8 @@ class Dartdoc {
     writeln('</div>');
 
     writeln('</div>');
+
+    _currentMember = null;
   }
 
   void docParamList(ContainerMirror enclosingType,
@@ -2012,6 +2019,23 @@ class Dartdoc {
       return anchor;
     }
 
+    DeclarationMirror declaration = currentMember;
+    if (declaration == null) declaration = currentType;
+    if (declaration == null) declaration = currentLibrary;
+    if (declaration != null) {
+      declaration = lookupQualifiedInScope(declaration, name);
+    }
+
+    if (declaration != null) {
+      if (declaration is TypeVariableMirror) {
+        return makeLink(typeUrl(declaration.owner));
+      } if (declaration is TypeMirror) {
+        return makeLink(typeUrl(declaration));
+      } else if (declaration is MethodMirror) {
+        return makeLink(memberUrl(declaration));
+      }
+    }
+
     // See if it's a parameter of the current method.
     if (currentMember is MethodMirror) {
       for (final parameter in currentMember.parameters) {