Fix getSourceReport's forceCompile option for unused classes.

runtime/vm/source_report.cc

Index: runtime/vm/source_report.cc
diff --git a/runtime/vm/source_report.cc b/runtime/vm/source_report.cc
index 1d3e818521487593de3d2a3e67e7f0fac3a30126..1e901afec171d7a6dd67eb872d7f7ab5afa23b3a 100644
--- a/runtime/vm/source_report.cc
+++ b/runtime/vm/source_report.cc
@@ -393,9 +393,31 @@ void SourceReport::VisitLibrary(JSONArray* jsarr, const Library& lib) {
   Class& cls = Class::Handle(zone());
   Array& functions = Array::Handle(zone());
   Function& func = Function::Handle(zone());
+  Script& script = Script::Handle(zone());
   ClassDictionaryIterator it(lib, ClassDictionaryIterator::kIteratePrivate);
   while (it.HasNext()) {
     cls = it.GetNextClass();
+    if (!cls.is_finalized()) {
+      if (compile_mode_ == kForceCompile) {
+        const Error& err = Error::Handle(cls.EnsureIsFinalized(thread()));
+        if (!err.IsNull()) {
+          // This class will get an error when finalized.  Skip it.

[rmacnak, 2016/04/25 23:28:34]

We don't report errors with kForceCompile? If we really don't want to abort on
error, shouldn't we at least mark this classes range as uncompiled like below?

+          continue;
+        }
+      } else {
+        // Emit one range for the whole uncompiled class.
+        script = cls.script();
+        const TokenPosition begin_pos = cls.token_pos();
+        const TokenPosition end_pos = cls.ComputeEndTokenPos();
+
+        JSONObject range(jsarr);
+        range.AddProperty("scriptIndex", GetScriptIndex(script));
+        range.AddProperty("startPos", begin_pos);
+        range.AddProperty("endPos", end_pos);
+        range.AddProperty("compiled", false);
+      }
+    }
+
     functions = cls.functions();
     for (int i = 0; i < functions.Length(); i++) {
       func ^= functions.At(i);