Disable load completion hacks flag, remove usages of the flag in chromium

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 601 matching lines @@
       'syzygy_optimize%': 0,
 
       # Enable hole punching for the protected video.
       'video_hole%': 0,
 
       # Temporary hack to allow us to unify blink's definitions of load
       # completion. blink uses a crazy set of constraints to determine load
       # completion, but only actually requires them for layout tests. However,
       # we need to maintain all the old behaviors while the plumbing is put in
       # place on both sides of the repo boundary.
-      'enable_load_completion_hacks%': 1,
+      'enable_load_completion_hacks%': 0,
 
       # Automatically select platforms under ozone. Turn this off to
       # build only explicitly selected platforms.
       'ozone_auto_platforms%': 1,
 
       # If this is set clang is used as host compiler, but not as target
       # compiler. Always do this by default.
       'host_clang%': 1,
 
       # Variables to control Link-Time Optimizations (LTO).
@@ skipping 5204 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',
   },
 }