[infer] Make infer respect external-packages param

Summary:
Fixes #1126

Different checks contain some ad hoc places that look at this param, but there is no systematic way to suppress this.
The centralized place that is filtering results is `reporting.ml`.

Note that this diff does not remove other usages, because they do more than mere filtering results.

Reviewed By: jvillard

Differential Revision: D16339655

fbshipit-source-id: afabdc97a

infer/src/backend/reporting.ml

@@ -36,12 +36,20 @@ let log_issue_from_summary severity summary ~node ~session ~loc ~ltr ?extras exn
     | _ ->
         false
   in
+  let is_java_external_package =
+    match procname with
+    | Typ.Procname.Java java_pname ->
+        Typ.Procname.Java.is_external java_pname
+    | _ ->
+        false
+  in
   let should_suppress_lint =
     Language.curr_language_is Java
     && Annotations.ia_is_suppress_lint
          (Summary.get_attributes summary).ProcAttributes.method_annotation.return
   in
-  if should_suppress_lint || is_java_generated_method then () (* Skip the reporting *)
+  if should_suppress_lint || is_java_generated_method || is_java_external_package then ()
+    (* Skip the reporting *)
   else
     let err_log = Summary.get_err_log summary in
     let clang_method_kind = Some attrs.clang_method_kind in

infer/src/nullsafe/NullabilitySuggest.ml

@@ -188,7 +188,16 @@ let checker {Callbacks.summary; exe_env} =
     let report_access_path ap udchain =
       match AccessPath.get_field_and_annotation ap proc_data.tenv with
       | Some (field_name, _) when is_outside_codebase proc_name field_name ->
-          (* Skip reporting when the field is outside the analyzed codebase *)
+          (* Skip reporting when the field is outside the analyzed codebase.
+             Note that we do similar filtering on high level which is common
+             for all checkers.
+             But this one is different: here we look NOT at the function
+             to be reported (the one that is using the field), but the root
+             cause (the field with the wrong annotation itself).
+             NOTE: Ideally we'd like to support such filtering in the way that
+                   is agnostic to particular checker, but it is not trivial to
+                   do, so let's do it in ad hoc way.
+           *)
           ()
       | Some (field_name, _) when Typ.Fieldname.Java.is_captured_parameter field_name ->
           (* Skip reporting when field comes from generated code *)