Enable by default hrefTranslate overriding of the language blocklist.

This CL turns on by default the overriding of the user's language
blocklist (e.g. the languages that the browser thinks the user is fluent
in) when deciding which translation actions to perform when a link with
hrefTranslate is clicked. For hrefTrasnalte link clicks from Google
domains, the user's language blocklist is overridden for the purposes of
automatic translation. For non-Google domains, the language blocklist is
overridden for the purposes of showing the translate UI.

Bug: 903416, 1131240
Change-Id: I4b6fb53a010098261f340f451c9aaaa6f339da0e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2533326
Auto-Submit: Scott Little <sclittle@chromium.org>
Commit-Queue: Megan Jablonski <megjablon@chromium.org>
Reviewed-by: Megan Jablonski <megjablon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826649}

components/translate/core/browser/translate_manager.cc

@@ -105,7 +105,7 @@ void MoveSkippedLanguagesToEndIfNecessary(
 }  // namespace
 
 const base::Feature kOverrideLanguagePrefsForHrefTranslate{
-    "OverrideLanguagePrefsForHrefTranslate", base::FEATURE_DISABLED_BY_DEFAULT};
+    "OverrideLanguagePrefsForHrefTranslate", base::FEATURE_ENABLED_BY_DEFAULT};
 
 const base::Feature kOverrideSitePrefsForHrefTranslate{
     "OverrideSitePrefsForHrefTranslate", base::FEATURE_DISABLED_BY_DEFAULT};
@@ -983,10 +983,14 @@ void TranslateManager::FilterForUserPrefs(
     }
     // Disable auto-translating the page for hrefTranslate unless hrefTranslate
     // is supposed to override the language blocklist for auto-translation as
-    // well.
-    if (!base::GetFieldTrialParamByFeatureAsBool(
+    // well. This is enabled by default, but the below if-statement also
+    // explicitly checks if the underlying base::Feature is enabled as well so
+    // that disabling the underlying base::Feature will also turn off forcing
+    // auto translation.
+    if (!base::FeatureList::IsEnabled(kOverrideLanguagePrefsForHrefTranslate) ||
+        !base::GetFieldTrialParamByFeatureAsBool(
             kOverrideLanguagePrefsForHrefTranslate, kForceAutoTranslateKey,
-            false)) {
+            true)) {
       decision->PreventAutoHrefTranslate();
     }