Added base::win::InitializeWindowClass() wrapper to make sure that window classes are properly asso…

base/win/wrapped_window_proc.cc

Index: base/win/wrapped_window_proc.cc
diff --git a/base/win/wrapped_window_proc.cc b/base/win/wrapped_window_proc.cc
index c94c5ae2544c37ee85add16125f705a69eb7a8b7..e66d42744cd09eece8feccf056d1a8f4a001d380 100644
--- a/base/win/wrapped_window_proc.cc
+++ b/base/win/wrapped_window_proc.cc
@@ -5,6 +5,8 @@
 #include "base/win/wrapped_window_proc.h"
 
 #include "base/atomicops.h"
+#include "base/logging.h"
+#include "base/process_util.h"
 
 namespace {
 
@@ -28,5 +30,34 @@ int CallExceptionFilter(EXCEPTION_POINTERS* info) {
                               EXCEPTION_CONTINUE_SEARCH;
 }
 
+BASE_EXPORT void InitializeWindowClass(
+    WNDCLASSEX* class_out,
+    const char16* class_name,
+    WNDPROC window_proc,
+    UINT style,
+    int class_extra,
+    int window_extra,
+    HCURSOR cursor,
+    HBRUSH background,
+    const char16* menu_name,
+    HICON large_icon,
+    HICON small_icon) {
+  class_out->cbSize = sizeof(WNDCLASSEX);
+  class_out->style = style;
+  class_out->lpfnWndProc = window_proc;
+  class_out->cbClsExtra = class_extra;
+  class_out->cbWndExtra = window_extra;
+  class_out->hInstance = base::GetModuleFromAddress(window_proc);
+  class_out->hIcon = large_icon;
+  class_out->hCursor = cursor;
+  class_out->hbrBackground = background;
+  class_out->lpszMenuName = menu_name;
+  class_out->lpszClassName = class_name;
+  class_out->hIconSm = small_icon;
+
+  // Check if |window_proc| is valid.
+  DCHECK(class_out->hInstance != NULL);
+}
+
 }  // namespace win
 }  // namespace base