Fix some -Wsign-compare fallout from changing container count member functions to return unsigned instead of bool.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211393 91177308-0d34-0410-b5e6-96231b3b80d8

unittests/ADT/DenseSetTest.cpp

@@ -24,7 +24,7 @@ TEST_F(DenseSetTest, DoubleEntrySetTest) {
   set.insert(0);
   set.insert(1);
   // Original failure was an infinite loop in this call:
-  EXPECT_EQ(0, set.count(2));
+  EXPECT_EQ(0u, set.count(2));
 }
 
 }