Quick Answers: Update default param value for translation

Bug: b/175747630
Test: None
Change-Id: I6e0c50ffa3a90a8088cfa21f3c1cf128f7fd412f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2636877
Auto-Submit: Yue Li <updowndota@chromium.org>
Reviewed-by: Jeroen Dhollander <jeroendh@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845189}

chromeos/components/quick_answers/utils/language_detector.cc

@@ -15,7 +15,7 @@ namespace {
 
 constexpr base::FeatureParam<double> kSelectedTextConfidenceThreshold{
     &features::kQuickAnswersTranslation, "selected_text_confidence_threshold",
-    /*default_value=*/0.7};
+    /*default_value=*/0.8};
 
 constexpr base::FeatureParam<double> kSurroundingTextConfidenceThreshold{
     &features::kQuickAnswersTranslation,