Move -Wno-switch in ICU to the target that actually needs it :-/

icu.gyp

 # Copyright (c) 2011 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.
 
 {
   'variables': {
     'use_system_icu%': 0,
     'icu_use_data_file_flag%': 0,
   },
   'target_defaults': {
@@ skipping 315 matching lines @@
                   # ICU uses its own deprecated functions.
                   '-Wno-deprecated-declarations',
                   # ICU prefers `a && b || c` over `(a && b) || c`.
                   '-Wno-logical-op-parentheses',
                   # ICU has some `unsigned < 0` checks.
                   '-Wno-tautological-compare',
                   # uspoof.h has a U_NAMESPACE_USE macro. That's a bug,
                   # the header should use U_NAMESPACE_BEGIN instead.
                   # http://bugs.icu-project.org/trac/ticket/9054
                   '-Wno-header-hygiene',
-                  # uresdata.c has switch(RES_GET_TYPE(x)) code. The
-                  # RES_GET_TYPE macro returns an UResType enum, but some switch
-                  # statement contains case values that aren't part of that
-                  # enum (e.g. URES_TABLE32 which is in UResInternalType). This
-                  # is on purpose.
-                  '-Wno-switch',
                 ],
               },
               'cflags': [
                 '-Wno-deprecated-declarations',
                 '-Wno-logical-op-parentheses',
                 '-Wno-tautological-compare',
                 '-Wno-header-hygiene',
-                '-Wno-switch',
               ],
             }],
           ],
         },
         {
           'target_name': 'icuuc',
           'type': '<(component)',
           'sources': [
             'source/common/bmpset.cpp',
             'source/common/brkeng.cpp',
@@ skipping 232 matching lines @@
             }],
             ['clang==1', {
               'xcode_settings': {
                 'WARNING_CFLAGS': [
                   # ICU uses its own deprecated functions.
                   '-Wno-deprecated-declarations',
                   # ICU prefers `a && b || c` over `(a && b) || c`.
                   '-Wno-logical-op-parentheses',
                   # ICU has some `unsigned < 0` checks.
                   '-Wno-tautological-compare',
+                  # uresdata.c has switch(RES_GET_TYPE(x)) code. The
+                  # RES_GET_TYPE macro returns an UResType enum, but some switch
+                  # statement contains case values that aren't part of that
+                  # enum (e.g. URES_TABLE32 which is in UResInternalType). This
+                  # is on purpose.
+                  '-Wno-switch',
                 ],
               },
               'cflags': [
                 '-Wno-deprecated-declarations',
                 '-Wno-logical-op-parentheses',
                 '-Wno-tautological-compare',
+                '-Wno-switch',
               ],
             }],
           ],
         },
       ],
     }, { # use_system_icu != 0
       'targets': [
         {
           'target_name': 'system_icu',
           'type': 'none',
@@ skipping 26 matching lines @@
         {
           'target_name': 'icuuc',
           'type': 'none',
           'dependencies': ['system_icu'],
           'export_dependent_settings': ['system_icu'],
         },
       ],
     }],
   ],
 }