webrtc: use correct cwd for running tests

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

Index: scripts/slave/recipes/webrtc/standalone.expected/tryserver_webrtc_linux_asan.json
diff --git a/scripts/slave/recipes/webrtc/standalone.expected/tryserver_webrtc_linux_asan.json b/scripts/slave/recipes/webrtc/standalone.expected/tryserver_webrtc_linux_asan.json
index 71752891c609cf201b8a5aef356e6f6d9551b4a1..9202392588a55be6b67323dd0c30e1174fd61f8b 100644
--- a/scripts/slave/recipes/webrtc/standalone.expected/tryserver_webrtc_linux_asan.json
+++ b/scripts/slave/recipes/webrtc/standalone.expected/tryserver_webrtc_linux_asan.json
@@ -286,6 +286,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/audio_decoder_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "audio_decoder_unittests"
   },
   {
@@ -313,6 +314,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/common_audio_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "common_audio_unittests"
   },
   {
@@ -340,6 +342,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/common_video_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "common_video_unittests"
   },
   {
@@ -367,6 +370,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/modules_tests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "modules_tests"
   },
   {
@@ -394,6 +398,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/modules_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "modules_unittests"
   },
   {
@@ -421,6 +426,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/peerconnection_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "peerconnection_unittests"
   },
   {
@@ -448,6 +454,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/rtc_media_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "rtc_media_unittests"
   },
   {
@@ -475,6 +482,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/rtc_pc_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "rtc_pc_unittests"
   },
   {
@@ -502,6 +510,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/rtc_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "rtc_unittests"
   },
   {
@@ -529,6 +538,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/system_wrappers_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "system_wrappers_unittests"
   },
   {
@@ -556,6 +566,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/test_support_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "test_support_unittests"
   },
   {
@@ -583,6 +594,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/tools_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "tools_unittests"
   },
   {
@@ -610,6 +622,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/video_engine_tests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "video_engine_tests"
   },
   {
@@ -637,6 +650,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/voice_engine_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "voice_engine_unittests"
   },
   {
@@ -664,6 +678,7 @@
       "[BUILDER_CACHE]/linux_asan/src/out/Release/xmllite_xmpp_unittests",
       "--"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "xmllite_xmpp_unittests"
   },
   {
@@ -690,6 +705,7 @@
       "--enable-lsan",
       "webrtc_nonparallel_tests"
     ],
+    "cwd": "[BUILDER_CACHE]/linux_asan",
     "name": "webrtc_nonparallel_tests"
   },
   {