[TTS] Add onTouchDown to GestureStateListener.

chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchFieldTrial.java

Index: chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchFieldTrial.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchFieldTrial.java b/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchFieldTrial.java
index c68b61ec5156bc14daf1333f85b56c121191d616..1d275bab68b080e5cc2bc4104b723239f5cef92d 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchFieldTrial.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchFieldTrial.java
@@ -34,7 +34,10 @@ public class ContextualSearchFieldTrial {
     private static final String DISABLE_SEARCH_TERM_RESOLUTION = "disable_search_term_resolution";
     private static final String WAIT_AFTER_TAP_DELAY_MS = "wait_after_tap_delay_ms";
 
-    // Translation.  All these members are private, except for usage by testing.
+    // ------------
+    // Translation.
+    // ------------
+    // All these members are private, except for usage by testing.
     // Master switch, needed to disable all translate code for Contextual Search in case of an
     // emergency.
     @VisibleForTesting
@@ -44,6 +47,9 @@ public class ContextualSearchFieldTrial {
     static final String ENABLE_ENGLISH_TARGET_TRANSLATION =
             "enable_english_target_translation";
 
+    // ---------------------------------------------
+    // Features for suppression or machine learning.
+    // ---------------------------------------------
     // TODO(donnd): remove all supporting code once short-lived data collection is done.
     private static final String SCREEN_TOP_SUPPRESSION_DPS = "screen_top_suppression_dps";
     private static final String ENABLE_BAR_OVERLAP_COLLECTION = "enable_bar_overlap_collection";
@@ -54,20 +60,25 @@ public class ContextualSearchFieldTrial {
             "enable_not_long_word_suppression";
     @VisibleForTesting
     static final String NOT_AN_ENTITY_SUPPRESSION_ENABLED = "enable_not_an_entity_suppression";
+    // The threshold for tap suppression based on duration.
+    private static final String TAP_DURATION_THRESHOLD_MS = "tap_duration_threshold_ms";
 
     private static final String MINIMUM_SELECTION_LENGTH = "minimum_selection_length";
 
+    // -----------------
+    // Disable switches.
+    // -----------------
     // Safety switch for disabling online-detection.  Also used to disable detection when running
     // tests.
     @VisibleForTesting
     static final String ONLINE_DETECTION_DISABLED = "disable_online_detection";
-
     private static final String DISABLE_AMP_AS_SEPARATE_TAB = "disable_amp_as_separate_tab";
-
-    // Machine Learning
+    // Disable logging for Machine Learning
     private static final String DISABLE_RANKER_LOGGING = "disable_ranker_logging";
 
-    // Privacy-related flags
+    // ----------------------
+    // Privacy-related flags.
+    // ----------------------
     private static final String DISABLE_SEND_HOME_COUNTRY = "disable_send_home_country";
     private static final String DISABLE_PAGE_CONTENT_NOTIFICATION =
             "disable_page_content_notification";
@@ -98,6 +109,7 @@ public class ContextualSearchFieldTrial {
     private static Boolean sContextualSearchUrlActionsEnabled;
     private static Boolean sIsRankerLoggingDisabled;
     private static Integer sWaitAfterTapDelayMs;
+    private static Integer sTapDurationThresholdMs;
 
     /**
      * Don't instantiate.
@@ -375,6 +387,18 @@ public class ContextualSearchFieldTrial {
         return sWaitAfterTapDelayMs.intValue();
     }
 
+    /**
+     * Gets a threshold for the duration of a tap gesture for categorization as brief or lengthy.
+     * @return The maximum amount of time in milliseconds for a tap gesture that's still considered
+     *         a very brief duration tap.
+     */
+    static int getTapDurationThresholdMs() {
+        if (sTapDurationThresholdMs == null) {
+            sTapDurationThresholdMs = getIntParamValueOrDefault(TAP_DURATION_THRESHOLD_MS, 0);
+        }
+        return sTapDurationThresholdMs.intValue();
+    }
+
     // ---------------------------
     // Feature-controlled Switches
     // ---------------------------