avoid 'may be used uninitialized' warnings in stack_sampling_profiler_unittest.cc

base/profiler/stack_sampling_profiler_unittest.cc

Index: base/profiler/stack_sampling_profiler_unittest.cc
diff --git a/base/profiler/stack_sampling_profiler_unittest.cc b/base/profiler/stack_sampling_profiler_unittest.cc
index 0037eb370f43400fa2c73ad299091d2b9dc9174e..a169c9d064d335a5e937ff5ef9e8eb69280616bf 100644
--- a/base/profiler/stack_sampling_profiler_unittest.cc
+++ b/base/profiler/stack_sampling_profiler_unittest.cc
@@ -272,7 +272,7 @@ NativeLibrary LoadOtherLibrary() {
                           << ": " << load_error.ToString();
   };
 
-  NativeLibrary library;
+  NativeLibrary library = nullptr;
   load(&library);
   return library;
 }