Revert the ConstantInt constructors back to their 2.5 forms where possible, thanks to contexts-on-types. More to come.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77011 91177308-0d34-0410-b5e6-96231b3b80d8

unittests/Support/ValueHandleTest.cpp

@@ -26,7 +26,7 @@ protected:
   std::auto_ptr<BitCastInst> BitcastV;
 
   ValueHandle() :
-    ConstantV(getGlobalContext().getConstantInt(Type::Int32Ty, 0)),
+    ConstantV(ConstantInt::get(Type::Int32Ty, 0)),
     BitcastV(new BitCastInst(ConstantV, Type::Int32Ty)) {
   }
 };