[DebugInfo] Change std::sort to llvm::sort in response to r327219

Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: echristo, zturner, samsonov

Reviewed By: echristo

Subscribers: JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D45134

llvm-svn: 328935
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index 3a974dd..2e36034 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -108,12 +108,12 @@
   // Sort the contributions so that any invalid ones are placed at
   // the start of the contributions vector. This way they are reported
   // first.
-  std::sort(Contributions.begin(), Contributions.end(),
-            [](const Optional<StrOffsetsContributionDescriptor> &L,
-               const Optional<StrOffsetsContributionDescriptor> &R) {
-              if (L && R) return L->Base < R->Base;
-              return R.hasValue();
-            });
+  llvm::sort(Contributions.begin(), Contributions.end(),
+             [](const Optional<StrOffsetsContributionDescriptor> &L,
+                const Optional<StrOffsetsContributionDescriptor> &R) {
+               if (L && R) return L->Base < R->Base;
+               return R.hasValue();
+             });
 
   // Uniquify contributions, as it is possible that units (specifically
   // type units in dwo or dwp files) share contributions. We don't want