NFC: Remove the ObjC1/ObjC2 distinction from clang (and related projects)

We haven't supported compiling ObjC1 for a long time (and never will again), so
there isn't any reason to keep these separate. This patch replaces
LangOpts::ObjC1 and LangOpts::ObjC2 with LangOpts::ObjC.

Differential revision: https://reviews.llvm.org/D53547

llvm-svn: 345637
diff --git a/clang-tools-extra/clang-tidy/objc/PropertyDeclarationCheck.cpp b/clang-tools-extra/clang-tidy/objc/PropertyDeclarationCheck.cpp
index 14e3ce1..d460c6b 100644
--- a/clang-tools-extra/clang-tidy/objc/PropertyDeclarationCheck.cpp
+++ b/clang-tools-extra/clang-tidy/objc/PropertyDeclarationCheck.cpp
@@ -201,9 +201,9 @@
 
 void PropertyDeclarationCheck::registerMatchers(MatchFinder *Finder) {
   // this check should only be applied to ObjC sources.
-  if (!getLangOpts().ObjC1 && !getLangOpts().ObjC2) {
+  if (!getLangOpts().ObjC)
     return;
-  }
+
   if (IncludeDefaultAcronyms) {
     EscapedAcronyms.reserve(llvm::array_lengthof(DefaultSpecialAcronyms) +
                             SpecialAcronyms.size());