Decouple modelTest from SourceCodeApi

Summary:
When I moved all Pysa access to Pyre environments into
PyrePysaEnvironment I punted on a few tests, but we really should
clean those up.

This one was accessing a TypeEnvironment and a SourceCodeApi, both of
which are implementation details of Pyre and shouldn't be leaked. We
already have a `source_of_qualifier` helper in the pyre pysa environment,
so let's use it.

The test code actually gets simpler as a bonus.

Reviewed By: rchen152

Differential Revision: D63547514

fbshipit-source-id: 0cd12bee1918b44c223624543851c1fae9c8a59e

source/interprocedural_analyses/taint/test/modelTest.ml

@@ -15,13 +15,9 @@ module PyrePysaEnvironment = Analysis.PyrePysaEnvironment
 
 let get_stubs_and_definitions ~source_file_name ~project =
   let pyre_api = Test.ScratchProject.pyre_pysa_read_only_api project in
-  let type_environment = Test.ScratchProject.type_environment project in
-  let source_code_api =
-    Analysis.TypeEnvironment.ReadOnly.get_untracked_source_code_api type_environment
-  in
   let qualifier = Ast.Reference.create (String.chop_suffix_exn source_file_name ~suffix:".py") in
   let ast_source =
-    Analysis.SourceCodeApi.source_of_qualifier source_code_api qualifier
+    PyrePysaEnvironment.ReadOnly.source_of_qualifier pyre_api qualifier
     |> fun option -> Option.value_exn option
   in
   let initial_callables =