Fix multiple issues with properties and top level variables (#1466)

* a little debug code

* intermediate state: things mostly work, but a lot of private constants showing up as broken links.

* intermediate state: debugging angular

* intermediate state.  things more or less work but are messy.

* Screenshot worthy.

* tests closer now

* Tests pass!

* fix up element search

* beginnings of unit tests

* Add new tests, and they pass.

* Add stranded files.

* Cleanup + dartfmt

* Minor cleanups

* More cleanups and simplification

* rebuild docs

* Add a test for extended docs for explicit getter/setter fields

* Test tweaks and dartfmt

* simplify an if statement

* recover some performance

* get back a little more performance

* dartfmt

* Fix minor problem with sdk build

* dartfmt

* Fix warning generation on non-canonical FieldElements

* Add review comments

Author: jcollins-g

lib/dartdoc.dart

@@ -220,9 +220,8 @@ class DartDoc {
       {String referredFrom}) {
     // Ordinarily this would go in [Package.warn], but we don't actually know what
     // ModelElement to warn on yet.
-    Locatable referredFromElement;
     Locatable warnOnElement;
-    Set<Locatable> referredFromElements;
+    Set<Locatable> referredFromElements = new Set();
     Set<Locatable> warnOnElements;
 
     // Make all paths relative to origin.
@@ -234,19 +233,14 @@ class DartDoc {
         referredFrom = path.relative(referredFrom, from: origin);
       }
       // Source paths are always relative.
-      referredFromElements = _hrefs[referredFrom];
+      if (_hrefs[referredFrom] != null) {
+        referredFromElements.addAll(_hrefs[referredFrom]);
+      }
     }
     warnOnElements = _hrefs[warnOn];
 
-    if (referredFromElements != null) {
-      if (referredFromElements.any((e) => e.isCanonical)) {
-        referredFromElement =
-            referredFromElements.firstWhere((e) => e.isCanonical);
-      } else {
-        // If we don't have a canonical element, just pick one.
-        referredFromElement =
-            referredFromElements.isEmpty ? null : referredFromElements.first;
-      }
+    if (referredFromElements.any((e) => e.isCanonical)) {
+      referredFromElements.removeWhere((e) => !e.isCanonical);
     }
     if (warnOnElements != null) {
       if (warnOnElements.any((e) => e.isCanonical)) {
@@ -257,12 +251,12 @@ class DartDoc {
       }
     }
 
-    if (referredFromElement == null && referredFrom == 'index.html')
-      referredFromElement = package;
+    if (referredFromElements.isEmpty && referredFrom == 'index.html')
+      referredFromElements.add(package);
     String message = warnOn;
     if (referredFrom == 'index.json') message = '$warnOn (from index.json)';
     package.warnOnElement(warnOnElement, kind,
-        message: message, referredFrom: referredFromElement);
+        message: message, referredFrom: referredFromElements);
   }
 
   void _doOrphanCheck(Package package, String origin, Set<String> visited) {

lib/src/html/html_generator_instance.dart

@@ -102,6 +102,7 @@ class HtmlGeneratorInstance implements HtmlOptions {
         // TODO(jcollins-g): consider refactor so that only the canonical
         // ModelElements show up in these lists
         if (!clazz.isCanonical) continue;
+
         generateClass(package, lib, clazz);
 
         for (var constructor in clazz.constructors) {

lib/src/markdown_processor.dart

@@ -292,10 +292,25 @@ MatchingLinkResult _getMatchingLinkElement(
   if (refModelElement != null) {
     return new MatchingLinkResult(refModelElement, null);
   }
-  refModelElement = new ModelElement.from(searchElement, refLibrary);
+  // From this point on, we haven't been able to find a canonical ModelElement.
+  // So in this case, just find any ModelElement we can.
+  Accessor getter;
+  Accessor setter;
+  if (searchElement is FieldElement) {
+    // TODO(jcollins-g): consolidate field element construction with inheritance
+    // checking.
+    if (searchElement.getter != null) {
+      getter = new ModelElement.from(searchElement.getter, refLibrary);
+    }
+    if (searchElement.setter != null) {
+      setter = new ModelElement.from(searchElement.setter, refLibrary);
+    }
+  }
+  refModelElement = new ModelElement.from(searchElement, refLibrary,
+      getter: getter, setter: setter);
   if (!refModelElement.isCanonical) {
-    refModelElement.warn(PackageWarning.noCanonicalFound,
-        referredFrom: element);
+    refModelElement
+        .warn(PackageWarning.noCanonicalFound, referredFrom: [element]);
     // Don't warn about doc references because that's covered by the no
     // canonical library found message.
     return new MatchingLinkResult(null, null, warn: false);