Change default Windows compiler to VS 2015

build/common.gypi

 # Copyright (c) 2012 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 5654 matching lines @@
           ],
           ['msvs_xtree_patched!=1', {
             # If xtree hasn't been patched, then we disable C4702. Otherwise,
             # it's enabled. This will generally only be true for system-level
             # installed Express users.
             'msvs_disabled_warnings': [
               4702, # unreachable code
             ],
           }],
         ],
+        # Add extra include directories here that need to be in front of the
+        # installed and packaged include directories. This may be needed in
+        # order to force a particular SDK version, such as to get VS 2013 to use
+        # the Windows 10 SDK. Beware of making the INCLUDE variable excessively
+        # long, and be sure to make corresponding changes to
+        # build\toolchain\win\setup_toolchain.py
         'msvs_system_include_dirs': [
-          '<(windows_sdk_path)/Include/10.0.10586.0/shared',

[scottmg, 2016/02/05 21:52:45]

Won't these be needed for DEPOT_TOOLS_WIN_TOOLCHAIN=0?

[brucedawson, 2016/02/05 22:28:19]

Only with VS 2013, which this switches away from (commenting here for
posterity).

-          '<(windows_sdk_path)/Include/10.0.10586.0/um',
-          '<(windows_sdk_path)/Include/10.0.10586.0/winrt',
-          '$(VSInstallDir)/VC/atlmfc/include',
         ],
         'msvs_cygwin_shell': 0,
         'msvs_disabled_warnings': [
           # C4091: 'typedef ': ignored on left of 'X' when no variable is
           #                    declared.
           # This happens in a number of Windows headers. Dumb.
           4091,
 
           # C4127: conditional expression is constant
           # This warning can in theory catch dead code and other problems, but
@@ skipping 703 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }