Enable DoH by default in Android UI

Followup to crrev.com/c/2429243. Chrome Java code for reading feature
params is done is such a way that it sets its own defaults instead of
the ones centrally defined with the feature params in chrome_features.cc

Bug: 878582,1098039
Change-Id: Ifef32ee702334e5d422b30490c472b165f3b48cf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2431790
Auto-Submit: Eric Orth <ericorth@chromium.org>
Commit-Queue: Dan McArdle <dmcardle@chromium.org>
Reviewed-by: Dan McArdle <dmcardle@chromium.org>
Cr-Commit-Position: refs/heads/master@{#810807}

chrome/browser/privacy/java/src/org/chromium/chrome/browser/privacy/secure_dns/SecureDnsBridge.java

@@ -46,7 +46,7 @@ static boolean isUiEnabled() {
         // Must match features::kDnsOverHttpsShowUiParam.
         final String showUiParam = "ShowUi";
         // Must match the default value for this param.
-        final boolean showUiParamDefault = false;
+        final boolean showUiParamDefault = true;
 
         return ChromeFeatureList.getFieldTrialParamByFeatureAsBoolean(
                 ChromeFeatureList.DNS_OVER_HTTPS, showUiParam, showUiParamDefault);