Include llvm::Optional in clang/Basic/LLVM.h

Post-commit CR feedback from Jordan Rose regarding r175594.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175679 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/BoolAssignmentChecker.cpp b/lib/StaticAnalyzer/Checkers/BoolAssignmentChecker.cpp
index 3ceb8c4..5169244 100644
--- a/lib/StaticAnalyzer/Checkers/BoolAssignmentChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/BoolAssignmentChecker.cpp
@@ -69,7 +69,7 @@
   // Get the value of the right-hand side.  We only care about values
   // that are defined (UnknownVals and UndefinedVals are handled by other
   // checkers).
-  llvm::Optional<DefinedSVal> DV = val.getAs<DefinedSVal>();
+  Optional<DefinedSVal> DV = val.getAs<DefinedSVal>();
   if (!DV)
     return;
     
@@ -86,7 +86,7 @@
     svalBuilder.evalBinOp(state, BO_GE, *DV, zeroVal,
                           svalBuilder.getConditionType());
 
-  llvm::Optional<DefinedSVal> greaterThanEqualToZero =
+  Optional<DefinedSVal> greaterThanEqualToZero =
       greaterThanOrEqualToZeroVal.getAs<DefinedSVal>();
 
   if (!greaterThanEqualToZero) {
@@ -122,7 +122,7 @@
     svalBuilder.evalBinOp(state, BO_LE, *DV, OneVal,
                           svalBuilder.getConditionType());
 
-  llvm::Optional<DefinedSVal> lessThanEqToOne =
+  Optional<DefinedSVal> lessThanEqToOne =
       lessThanEqToOneVal.getAs<DefinedSVal>();
 
   if (!lessThanEqToOne) {