[GN] Add -Wno-unused-result on Linux and Android.

BUILD.gn

 # Copyright 2014 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.
 
 import("//third_party/icu/config.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
 
@@ skipping 49 matching lines @@
       "/wd4068",  # Unknown pragmas.
       "/wd4267",  # Conversion from size_t on 64-bits.
       "/wd4996",  # Deprecated functions.
     ]
   } else if (is_linux || is_android) {
     cflags += [
       # Since ICU wants to internally use its own deprecated APIs, don't
       # complain about it.
       "-Wno-deprecated-declarations",
       "-Wno-unused-function",
+
+      # fread is used in putil.cpp without checking the return value.
+      "-Wno-unused-result",
     ]
   }
   if (is_clang) {
     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",
@@ skipping 536 matching lines @@
         sources = [
           "android/icudtl_dat.S",
         ]
       } else {
         assert(false, "No icu data for this platform")
       }
       defines = [ "U_HIDE_DATA_SYMBOL" ]
     }
   }
 }