win: Remove GetModuleFromAddress, deduplicate __ImageBase code.

base/win/scoped_handle_test_dll.cc

Index: base/win/scoped_handle_test_dll.cc
diff --git a/base/win/scoped_handle_test_dll.cc b/base/win/scoped_handle_test_dll.cc
index e6e1215d5990aab5c8b1988699f78c69300b1f19..440a4ca7658c83619baf404b5bf0d0f2d4a078c3 100644
--- a/base/win/scoped_handle_test_dll.cc
+++ b/base/win/scoped_handle_test_dll.cc
@@ -6,11 +6,9 @@
 
 #include <vector>
 
+#include "base/win/current_module.h"
 #include "base/win/scoped_handle.h"
 
-// http://blogs.msdn.com/oldnewthing/archive/2004/10/25/247180.aspx
-extern "C" IMAGE_DOS_HEADER __ImageBase;
-
 namespace base {
 namespace win {
 namespace testing {
@@ -95,7 +93,7 @@ bool InternalRunLocationTest() {
     return false;
 
   // Get my module
-  HMODULE my_module = reinterpret_cast<HMODULE>(&__ImageBase);
+  HMODULE my_module = CURRENT_MODULE();
   if (!my_module)
     return false;