Move assert.h/assert.cc from runtime/vm to runtime/platform

runtime/vm/compiler_test.cc

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// 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 "platform/assert.h"
 #include "vm/compiler.h"
-
-#include "vm/assert.h"
 #include "vm/object.h"
 #include "vm/unit_test.h"
 
 namespace dart {
 
 // Compiler only implemented on IA32 and X64 now.
 #if defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64)
 
 TEST_CASE(CompileScript) {
   const char* kScriptChars =
@@ skipping 37 matching lines @@
       Function::Handle(cls.LookupStaticFunction(function_moo_name));
   EXPECT(!function_moo.IsNull());
 
   EXPECT(CompilerTest::TestCompileFunction(function_moo));
   EXPECT(function_moo.HasCode());
 }
 
 #endif  // TARGET_ARCH_IA32 || TARGET_ARCH_X64
 
 }  // namespace dart