Add testing connfig for Smart download location suggestion

BUG=1136562

Change-Id: I474995a05ce42974e2a38cbb34e93a366cd8fc34
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2588302
Commit-Queue: Min Qin <qinmin@chromium.org>
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Cr-Commit-Position: refs/heads/master@{#837348}

chrome/android/javatests/src/org/chromium/chrome/browser/download/DownloadLocationChangeTest.java

@@ -156,6 +156,7 @@ public class DownloadLocationChangeTest implements CustomMainActivityStart {
     @MediumTest
     @Feature({"Downloads"})
     @Features.EnableFeatures(ChromeFeatureList.DOWNLOADS_LOCATION_CHANGE)
+    @Features.DisableFeatures(ChromeFeatureList.SMART_SUGGESTION_FOR_LARGE_DOWNLOADS)
     public void testNoDialogWithoutSDCard() {
         int currentCallCount = mDownloadTestRule.getChromeDownloadCallCount();
         startDownload(/*hasSDCard=*/false);

testing/variations/fieldtrial_testing_config.json

@@ -6801,6 +6801,21 @@
             ]
         }
     ],
+    "SmartSuggestionForLargeDownloads": [
+        {
+            "platforms": [
+                "android"
+            ],
+            "experiments": [
+                {
+                    "name": "Enabled",
+                    "enable_features": [
+                        "SmartSuggestionForLargeDownloads"
+                    ]
+                }
+            ]
+        }
+    ],
     "SmoothnessModeForAnimatedScrolls": [
         {
             "platforms": [