Follow-up fix to my change to IsPowerOfTwo: Alignment of one means no alignment, not zero.

runtime/vm/assembler_ia32_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.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/assembler.h"
 #include "vm/os.h"
 #include "vm/unit_test.h"
@@ skipping 654 matching lines @@
 
 
 ASSEMBLER_TEST_RUN(Exchange, test) {
   typedef int (*Exchange)();
   EXPECT_EQ(987654321 - 123456789, reinterpret_cast<Exchange>(test->entry())());
 }
 
 
 static int ComputeStackSpaceReservation(int needed, int fixed) {
   static const int kFrameAlignment = OS::ActivationFrameAlignment();
-  return (kFrameAlignment > 0)
+  return (kFrameAlignment > 1)
       ? Utils::RoundUp(needed + fixed, kFrameAlignment) - fixed
       : needed;
 }
 
 
 static int LeafReturn42() {
   return 42;
 }
 
 
@@ skipping 2167 matching lines @@
                      FieldAddress(ECX, GrowableObjectArray::data_offset()),
                      EAX);
   __ popl(EAX);
   __ popl(CTX);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32