Fixing pixel2 swarming pool

NOTRY=true

Bug: 817872
Change-Id: I4cacf33aa0411fb648e3396ca047aa0ed8773123
Reviewed-on: https://chromium-review.googlesource.com/1044284Reviewed-by: Ned Nguyen <nednguyen@google.com>
Commit-Queue: Emily Hanley <eyaich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556081}

testing/buildbot/chromium.perf.fyi.json

@@ -723,7 +723,7 @@
               "device_os": "O",
               "device_type": "walleye",
               "os": "Android",
-              "pool": "chrome.test.perf-fyi"
+              "pool": "chrome.tests.perf-fyi"
             }
           ],
           "expiration": 36000,
@@ -771,7 +771,7 @@
               "device_os": "O",
               "device_type": "walleye",
               "os": "Android",
-              "pool": "chrome.test.perf-webview-fyi"
+              "pool": "chrome.tests.perf-webview-fyi"
             }
           ],
           "expiration": 36000,

tools/perf/core/perf_data_generator.py

@@ -1034,7 +1034,7 @@ NEW_PERF_RECIPE_FYI_TESTERS = {
       ],
       'platform': 'android-webview',
       'dimension': {
-        'pool': 'chrome.test.perf-webview-fyi',
+        'pool': 'chrome.tests.perf-webview-fyi',
         'os': 'Android',
         'device_type': 'walleye',
         'device_os': 'O'
@@ -1051,7 +1051,7 @@ NEW_PERF_RECIPE_FYI_TESTERS = {
       ],
       'platform': 'android',
       'dimension': {
-        'pool': 'chrome.test.perf-fyi',
+        'pool': 'chrome.tests.perf-fyi',
         'os': 'Android',
         'device_type': 'walleye',
         'device_os': 'O'