Optimize GetPathForVectorIcon*, save ~290 KB on disk

chrome/app/vector_icons/vector_icons.cc.template

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // vector_icons.cc.template is used to generate vector_icons.cc. Edit the former
 // rather than the latter.
 
 #include "chrome/app/vector_icons/vector_icons.h"
 
 #include "base/logging.h"
 #include "ui/gfx/vector_icon_types.h"
 
 #define PATH_ELEMENT_TEMPLATE(path_name, ...) \
-static gfx::PathElement path_name[] = {__VA_ARGS__};
+static constexpr gfx::PathElement path_name[] = {__VA_ARGS__};
 
 #define VECTOR_ICON_TEMPLATE(icon_name, path_name, path_name_1x) \
 const gfx::VectorIcon icon_name = { path_name , path_name_1x };

[grt (UTC plus 2), 2017/02/07 07:46:15]

why not here as well? it may not have the same wondrous gains as the macro
above, but it seems equally valid for this to be static constexpr (unless i'm
missing something).

[brucedawson, 2017/02/21 17:52:12]

The only reason it wasn't added was because it wasn't needed. Agreed that it
would be valid and appropriate. At some point we should do an aggressive pass
over Chrome's source code to add constexpr to thousands of places. If VC++ 2017
gets a constexpr feature that I'm hoping for then this process can be pushed
much further.

So, we could add constexpr here (the static is actually unneeded as const and
constexpr both imply static - I should have removed the static from line 14) but
I'm inclined to treat doing so so as no higher priority than the other
~thousands of const globals.

 
 using namespace gfx;
 
 TEMPLATE_PLACEHOLDER