Field Trial Testing Config - Update for Omnibox Experiments

Split the omnibox entry into desktop, android, and iOS.

For each separate target,
add all missing features that are being tested in beta or stable.

The only feature I skipped was entity suggestions, which as I understand
it is being revised / reimplemented, so it's not something that should
be actively tested.  (Indeed, we probably should get rid of the
experiment configs that are currently running with this feature, lest
we end up start running a code path in the wild that isn't yet
finished being revised.)

Change-Id: I3c8826c1d00613242b1ab77f66e22574f6532bb0
Reviewed-on: https://chromium-review.googlesource.com/1000029
Commit-Queue: Mark Pearson <mpearson@chromium.org>
Reviewed-by: Justin Donnelly <jdonnelly@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550077}

testing/variations/fieldtrial_testing_config.json

@@ -2274,24 +2274,54 @@
     "OmniboxBundledExperimentV1": [
         {
             "platforms": [
-                "android",
                 "chromeos",
-                "ios",
                 "linux",
                 "mac",
                 "win"
             ],
             "experiments": [
                 {
-                    "name": "UIExperiments",
+                    "name": "DesktopExperiments",
                     "params": {
                         "UIVerticalMargin": "8"
                     },
                     "enable_features": [
                         "OmniboxBreakWordsAtUnderscores",
+                        "OmniboxDisplayTitleForCurrentUrl",
+                        "OmniboxTailSuggestions",
                         "OmniboxUIExperimentShowSuggestionFavicons",
                         "OmniboxUIExperimentSwapTitleAndUrl",
-                        "OmniboxUIExperimentVerticalMargin"
+                        "OmniboxUIExperimentVerticalMargin",
+                        "ZeroSuggestRedirectToChrome",
+                        "ZeroSuggestSwapTitleAndUrl"
+                    ]
+                }
+            ]
+        },
+        {
+            "platforms": [
+                "android"
+            ],
+            "experiments": [
+                {
+                    "name": "AndroidExperiments",
+                    "enable_features": [
+                        "OmniboxBreakWordsAtUnderscores",
+                        "OmniboxDisplayTitleForCurrentUrl"
+                    ]
+                }
+            ]
+        },
+        {
+            "platforms": [
+                "ios"
+            ],
+            "experiments": [
+                {
+                    "name": "iOSExperiments",
+                    "enable_features": [
+                        "OmniboxBreakWordsAtUnderscores",
+                        "OmniboxDisplayTitleForCurrentUrl"
                     ]
                 }
             ]