webrtc: run tests in the checkout directory

scripts/slave/recipes/webrtc/standalone.expected/client_webrtc_linux64_debug_forced.json

Index: scripts/slave/recipes/webrtc/standalone.expected/client_webrtc_linux64_debug_forced.json
diff --git a/scripts/slave/recipes/webrtc/standalone.expected/client_webrtc_linux64_debug_forced.json b/scripts/slave/recipes/webrtc/standalone.expected/client_webrtc_linux64_debug_forced.json
index 1e353aec9ee62ce3739e71028b099a39e6ca6063..db69ed904328edbce9f13c378afd6669fba02e9e 100644
--- a/scripts/slave/recipes/webrtc/standalone.expected/client_webrtc_linux64_debug_forced.json
+++ b/scripts/slave/recipes/webrtc/standalone.expected/client_webrtc_linux64_debug_forced.json
@@ -254,7 +254,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/audio_decoder_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "audio_decoder_unittests"
   },
   {
@@ -280,7 +280,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/common_audio_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "common_audio_unittests"
   },
   {
@@ -306,7 +306,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/common_video_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "common_video_unittests"
   },
   {
@@ -332,7 +332,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/modules_tests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "modules_tests"
   },
   {
@@ -358,7 +358,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/modules_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "modules_unittests"
   },
   {
@@ -384,7 +384,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/peerconnection_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "peerconnection_unittests"
   },
   {
@@ -410,7 +410,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/rtc_media_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "rtc_media_unittests"
   },
   {
@@ -436,7 +436,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/rtc_pc_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "rtc_pc_unittests"
   },
   {
@@ -462,7 +462,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/rtc_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "rtc_unittests"
   },
   {
@@ -488,7 +488,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/system_wrappers_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "system_wrappers_unittests"
   },
   {
@@ -514,7 +514,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/test_support_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "test_support_unittests"
   },
   {
@@ -540,7 +540,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/tools_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "tools_unittests"
   },
   {
@@ -566,7 +566,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/video_engine_tests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "video_engine_tests"
   },
   {
@@ -592,7 +592,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/voice_engine_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "voice_engine_unittests"
   },
   {
@@ -618,7 +618,7 @@
       "[BUILDER_CACHE]/Linux64_Debug/src/out/Debug/xmllite_xmpp_unittests",
       "--"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "xmllite_xmpp_unittests"
   },
   {
@@ -646,7 +646,7 @@
       "--revision=f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9",
       "webrtc_nonparallel_tests"
     ],
-    "cwd": "[BUILDER_CACHE]/Linux64_Debug",
+    "cwd": "[BUILDER_CACHE]/Linux64_Debug/src",
     "name": "webrtc_nonparallel_tests"
   },
   {