Fixes Android build by using C++ math header instead of C one.

runtime/vm/object_test.cc

 // Copyright (c) 2012, 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.
 
-// TODO(zra): Remove when tests are ready to enable.
 #include "platform/globals.h"
 
 #include "vm/assembler.h"
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
 #include "vm/isolate.h"
 #include "vm/object.h"
@@ skipping 504 matching lines @@
     const Double& dbl1 = Double::Handle(Double::New(dbl_const));
     const Double& dbl2 = Double::Handle(Double::New(dbl_const));
     EXPECT(dbl1.OperatorEquals(dbl2));
     EXPECT(dbl1.IsIdenticalTo(dbl2));
     EXPECT(dbl1.CanonicalizeEquals(dbl2));
     const Double& dbl3 = Double::Handle(Double::New(3.3));
     EXPECT(!dbl1.OperatorEquals(dbl3));
     EXPECT(!dbl1.OperatorEquals(Smi::Handle(Smi::New(3))));
     EXPECT(!dbl1.OperatorEquals(Double::Handle()));
     const Double& nan0 = Double::Handle(Double::New(NAN));
-    EXPECT(isnan(nan0.value()));
+    EXPECT(std::isnan(nan0.value()));
     EXPECT(nan0.IsIdenticalTo(nan0));
     EXPECT(nan0.CanonicalizeEquals(nan0));
     EXPECT(!nan0.OperatorEquals(nan0));
     const Double& nan1 = Double::Handle(
         Double::New(bit_cast<double>(kMaxUint64 - 0)));
     const Double& nan2 = Double::Handle(
         Double::New(bit_cast<double>(kMaxUint64 - 1)));
-    EXPECT(isnan(nan1.value()));
-    EXPECT(isnan(nan2.value()));
+    EXPECT(std::isnan(nan1.value()));
+    EXPECT(std::isnan(nan2.value()));
     EXPECT(!nan1.IsIdenticalTo(nan2));
     EXPECT(!nan1.CanonicalizeEquals(nan2));
     EXPECT(!nan1.OperatorEquals(nan2));
   }
   {
     const String& dbl_str0 = String::Handle(String::New("bla"));
     const Double& dbl0 = Double::Handle(Double::New(dbl_str0));
     EXPECT(dbl0.IsNull());
 
     const String& dbl_str1 = String::Handle(String::New("2.0"));
@@ skipping 3550 matching lines @@
   EXPECT_VALID(h_result);
   Integer& result = Integer::Handle();
   result ^= Api::UnwrapHandle(h_result);
   String& foo = String::Handle(String::New("foo"));
   Integer& expected = Integer::Handle();
   expected ^= foo.HashCode();
   EXPECT(result.IsIdenticalTo(expected));
 }
 
 }  // namespace dart