fix armv7 non-neon webrtc builds

webrtc/common_audio/BUILD.gn

Index: webrtc/common_audio/BUILD.gn
diff --git a/webrtc/common_audio/BUILD.gn b/webrtc/common_audio/BUILD.gn
index 3d4a3321a0ed68cbe45c9ad9507ba6bddc27a7e0..e6d14ca725f7301fb6d90d7c3eb1020b0049a5cd 100644
--- a/webrtc/common_audio/BUILD.gn
+++ b/webrtc/common_audio/BUILD.gn
@@ -129,7 +129,7 @@ source_set("common_audio") {
       "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 {