Re-land "Remove <(webrtc_root) from source file entries."

Changes differing from https://webrtc-codereview.appspot.com/37859004:
* I put the include_tests==1 stuff of audio_coding.gypi in its
  own audio_coding_tests.gypi file, including the Android and isolate
  targets which were incorrectly located in the previous CL
* I moved the bwe utilities in remote_bitrate_estimator.gypi
  into include_tests==1 since they depend on test.gyp after I
  cleaned up the duplicated inclusion of rtp_file_reader.cc

R=stefan@webrtc.org
TBR=tina.legrand@webrtc.org
TESTED=Passing gyp and compile using:
webrtc/build/gyp_webrtc -Dinclude_tests=1
webrtc/build/gyp_webrtc -Dinclude_tests=0
I also setup a Chromium checkout with my checkout mounted in
third_party/webrtc and ran build/gyp_chromium successfully.

BUG=4185

Review URL: https://webrtc-codereview.appspot.com/33159004

Cr-Commit-Position: refs/heads/master@{#8205}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8205 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/modules.gyp b/webrtc/modules/modules.gyp
index 691f308..23ee29f 100644
--- a/webrtc/modules/modules.gyp
+++ b/webrtc/modules/modules.gyp
@@ -9,17 +9,7 @@
 {
   'includes': [
     '../build/common.gypi',
-    'audio_coding/codecs/interfaces.gypi',
-    'audio_coding/codecs/cng/cng.gypi',
-    'audio_coding/codecs/g711/g711.gypi',
-    'audio_coding/codecs/g722/g722.gypi',
-    'audio_coding/codecs/ilbc/ilbc.gypi',
-    'audio_coding/codecs/isac/main/source/isac.gypi',
-    'audio_coding/codecs/isac/fix/source/isacfix.gypi',
-    'audio_coding/codecs/pcm16b/pcm16b.gypi',
-    'audio_coding/codecs/red/red.gypi',
-    'audio_coding/main/acm2/audio_coding_module.gypi',
-    'audio_coding/neteq/neteq.gypi',
+    'audio_coding/audio_coding.gypi',
     'audio_conference_mixer/source/audio_conference_mixer.gypi',
     'audio_device/audio_device.gypi',
     'audio_processing/audio_processing.gypi',
@@ -37,14 +27,9 @@
     'video_render/video_render.gypi',
   ],
   'conditions': [
-    ['include_opus==1', {
-      'includes': ['audio_coding/codecs/opus/opus.gypi',],
-    }],
     ['include_tests==1', {
       'includes': [
-        'audio_coding/codecs/isac/isac_test.gypi',
-        'audio_coding/codecs/isac/isacfix_test.gypi',
-        'audio_coding/codecs/tools/audio_codec_speed_tests.gypi',
+        'audio_coding/audio_coding_tests.gypi',
         'audio_processing/audio_processing_tests.gypi',
         'rtp_rtcp/test/testFec/test_fec.gypi',
         'video_coding/main/source/video_coding_test.gypi',
@@ -101,6 +86,7 @@
             '<(webrtc_root)/test/test.gyp:frame_generator',
             '<(webrtc_root)/test/test.gyp:rtp_test_utils',
             '<(webrtc_root)/test/test.gyp:test_support_main',
+            '<(webrtc_root)/tools/tools.gyp:agc_test_utils',
           ],
           'sources': [
             'audio_coding/codecs/cng/audio_encoder_cng_unittest.cc',
@@ -175,7 +161,6 @@
             'audio_processing/agc/pitch_internal_unittest.cc',
             'audio_processing/agc/pole_zero_filter_unittest.cc',
             'audio_processing/agc/standalone_vad_unittest.cc',
-            'audio_processing/agc/test/test_utils.cc',
             'audio_processing/beamformer/complex_matrix_unittest.cc',
             'audio_processing/beamformer/covariance_matrix_generator_unittest.cc',
             'audio_processing/beamformer/matrix_unittest.cc',