Convert cacheinvalidation_unittests to run exclusively on Swarming

testing/buildbot/chromium.win.json

Index: testing/buildbot/chromium.win.json
diff --git a/testing/buildbot/chromium.win.json b/testing/buildbot/chromium.win.json
index 91c71ef071d2d3a6cc03a8d661bf2389a44db17f..6e1ece16e1d019c80fdc2dbad7cda06187f70a2e 100644
--- a/testing/buildbot/chromium.win.json
+++ b/testing/buildbot/chromium.win.json
@@ -30,6 +30,9 @@
         "test": "browser_tests"
       },
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "cacheinvalidation_unittests"
       },
       {
@@ -295,6 +298,9 @@
         "test": "browser_tests"
       },
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "cacheinvalidation_unittests"
       },
       {
@@ -697,6 +703,9 @@
         "test": "browser_tests"
       },
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "cacheinvalidation_unittests"
       },
       {
@@ -988,6 +997,9 @@
         "test": "browser_tests"
       },
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "cacheinvalidation_unittests"
       },
       {
@@ -1407,6 +1419,9 @@
         "test": "browser_tests"
       },
       {
+        "swarming": {
+          "can_use_on_swarming_builders": true
+        },
         "test": "cacheinvalidation_unittests"
       },
       {