Fix Android build warnings

runtime/vm/profiler_test.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/assert.h"
 
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"
 #include "vm/globals.h"
 #include "vm/profiler.h"
@@ skipping 2306 matching lines @@
     // executing one (i == 0) are actually return addresses. Return addresses
     // are one byte beyond the call instruction that is executing. The profiler
     // accounts for this and subtracts one from these addresses when querying
     // inline and token position ranges. To be consistent with real stack
     // traces, we add one byte to all PCs except the executing one.
     // See OffsetForPC in profiler_service.cc for more context.
     const intptr_t return_address_offset = i > 0 ? 1 : 0;
     sample->SetAt(i, pc_offsets[i] + return_address_offset);
     i++;
   }
-  sample->SetAt(i, NULL);
+  sample->SetAt(i, 0);
 }
 
 
 static uword FindPCForTokenPosition(const Code& code,
                                     const CodeSourceMap& code_source_map,
                                     TokenPosition tp) {
   CodeSourceMap::Iterator it(code_source_map);
 
   while (it.MoveNext()) {
     if (it.TokenPos() == tp) {
@@ skipping 156 matching lines @@
   EXPECT_SUBSTRING("\"positions\":[\"TempMove\",39]", js.ToCString());
   // Verify exclusive ticks in main.
   EXPECT_SUBSTRING("\"exclusiveTicks\":[1,0]", js.ToCString());
   // Verify inclusive ticks in main.
   EXPECT_SUBSTRING("\"inclusiveTicks\":[1,2]", js.ToCString());
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart