fix armv7 non-neon webrtc builds

webrtc/common_audio/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/arm.gni")
 import("../build/webrtc.gni")
@@ skipping 111 matching lines @@
       deps += [ "//third_party/openmax_dl/dl" ]
     }
   }
 
   if (current_cpu == "arm") {
     sources += [
       "signal_processing/complex_bit_reverse_arm.S",
       "signal_processing/spl_sqrt_floor_arm.S",
     ]
 
-    if (arm_version >= 7) {
+    if (rtc_build_armv7_neon) {

[Andrew MacDonald, 2015/06/17 05:36:32]

This shouldn't change anything; it amounts to the same condition:
current_cpu == "arm" && arm_version >= 7
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/webrtc...

[Mostyn Bramley-Moore, 2015/06/17 07:42:26]

"arm_version>=7" is wrong because neon is optional in armv7. 
rtc_build_armv7_neon is better because it can be overridden independently of the
arm_version argument.  Though perhaps it should be renamed to rtc_build_arm_neon
and the defaults improved a bit in webrtc.gni ?

[jridges, 2015/06/17 15:56:49]

This clause is doing two independent things which should be separated into two
clauses. "arm_version >= 7" is correct for choosing which filter_ar_fast_q12
source to use, but something like "rtc_build_armv7_neon" is correct for setting
the deps.

       deps += [ ":common_audio_neon" ]
       sources += [ "signal_processing/filter_ar_fast_q12_armv7.S" ]
     } else {
       sources += [ "signal_processing/filter_ar_fast_q12.c" ]
     }
   }
 
   if (current_cpu == "arm64") {
     deps += [ ":common_audio_neon" ]
   }
@@ skipping 88 matching lines @@
 
     # Disable LTO in audio_processing_neon target due to compiler bug.
     if (rtc_use_lto) {
       cflags -= [
         "-flto",
         "-ffat-lto-objects",
       ]
     }
   }
 }