Add configuration for {Mac,Linux,Win} Builder (dbg).

Add configuration for debug bots to chromium.webrtc.fyi JSON spec.

Bug: None
Change-Id: If8ec76c69c9ab365d42447520a8c02addbd2f6bf
Reviewed-on: https://chromium-review.googlesource.com/800177
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Patrik Höglund <phoglund@chromium.org>
Cr-Commit-Position: refs/heads/master@{#520763}

testing/buildbot/chromium.webrtc.fyi.json

@@ -19,14 +19,47 @@
       "all"
     ]
   },
+  "Linux Builder (dbg)": {
+    "additional_compile_targets": [
+      "all",
+      "browser_tests",
+      "capture_unittests",
+      "content_browsertests",
+      "content_unittests",
+      "jingle_unittests",
+      "remoting_unittests"
+    ]
+  },
   "Mac Builder": {
     "additional_compile_targets": [
       "all"
     ]
   },
+  "Mac Builder (dbg)": {
+    "additional_compile_targets": [
+      "all",
+      "browser_tests",
+      "capture_unittests",
+      "content_browsertests",
+      "content_unittests",
+      "jingle_unittests",
+      "remoting_unittests"
+    ]
+  },
   "Win Builder": {
     "additional_compile_targets": [
       "all"
     ]
+  },
+  "Win Builder (dbg)": {
+    "additional_compile_targets": [
+      "all",
+      "browser_tests",
+      "capture_unittests",
+      "content_browsertests",
+      "content_unittests",
+      "jingle_unittests",
+      "remoting_unittests"
+    ]
   }
 }