Revert "Track expression language from one place in ClangExpressionParser"

r263099 seems to have broken some OSX tests

llvm-svn: 263107
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
index c84b825..d91fb7a 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
@@ -157,7 +157,7 @@
 
     // 1. Create a new compiler instance.
     m_compiler.reset(new CompilerInstance());
-    m_language = expr.Language(); // defaults to lldb::eLanguageTypeUnknown
+    lldb::LanguageType frame_lang = expr.Language(); // defaults to lldb::eLanguageTypeUnknown
     bool overridden_target_opts = false;
     lldb_private::LanguageRuntime *lang_rt = nullptr;
     lldb::TargetSP target_sp;
@@ -176,14 +176,14 @@
 
     // Make sure the user hasn't provided a preferred execution language
     // with `expression --language X -- ...`
-    if (frame && m_language == lldb::eLanguageTypeUnknown)
-        m_language = frame->GetLanguage();
+    if (frame && frame_lang == lldb::eLanguageTypeUnknown)
+        frame_lang = frame->GetLanguage();
 
-    if (m_language != lldb::eLanguageTypeUnknown)
+    if (frame_lang != lldb::eLanguageTypeUnknown)
     {
-        lang_rt = exe_scope->CalculateProcess()->GetLanguageRuntime(m_language);
+        lang_rt = exe_scope->CalculateProcess()->GetLanguageRuntime(frame_lang);
         if (log)
-            log->Printf("Frame has language of type %s", Language::GetNameForLanguageType(m_language));
+            log->Printf("Frame has language of type %s", Language::GetNameForLanguageType(frame_lang));
     }
 
     // 2. Configure the compiler with a set of default options that are appropriate
@@ -263,7 +263,9 @@
     assert (m_compiler->hasTarget());
 
     // 5. Set language options.
-    switch (m_language)
+    lldb::LanguageType language = expr.Language();
+
+    switch (language)
     {
     case lldb::eLanguageTypeC:
     case lldb::eLanguageTypeC89: