Added LLVM_FALLTHROUGH to address warning: this statement may fall through. NFC.

llvm-svn: 304870
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 8cd7efb..7e5e2a1 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -4020,6 +4020,7 @@
       }
     }
     // fallthrough
+    LLVM_FALLTHROUGH;
   }
   default: {
     // We have a template type parameter but the template argument
@@ -7594,6 +7595,7 @@
         return false;
       }
       // Fall through
+      LLVM_FALLTHROUGH;
 
     case TSK_ExplicitInstantiationDeclaration:
     case TSK_ExplicitInstantiationDefinition:
@@ -9379,6 +9381,7 @@
   }
   // Fall through to create a dependent typename type, from which we can recover
   // better.
+  LLVM_FALLTHROUGH;
 
   case LookupResult::NotFoundInCurrentInstantiation:
     // Okay, it's a member of an unknown instantiation.