Revert 147988 - Upgrade AlignedMemory to support dynamic allocations.

base/compiler_specific.h

Index: base/compiler_specific.h
===================================================================
--- base/compiler_specific.h	(revision 148015)
+++ base/compiler_specific.h	(working copy)
@@ -114,13 +114,11 @@
 #define ALIGNAS(byte_alignment) __attribute__((aligned(byte_alignment)))
 #endif
 
-// Return the byte alignment of the given type (available at compile time).  Use
-// sizeof(type) prior to checking __alignof to workaround Visual C++ bug:
-// http://goo.gl/isH0C
+// Return the byte alignment of the given type (available at compile time).
 // Use like:
 //   ALIGNOF(int32)  // this would be 4
 #if defined(COMPILER_MSVC)
-#define ALIGNOF(type) (sizeof(type) - sizeof(type) + __alignof(type))
+#define ALIGNOF(type) __alignof(type)
 #elif defined(COMPILER_GCC)
 #define ALIGNOF(type) __alignof__(type)
 #endif