[TTS] Add some initial signals for Tap in content.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/TapWordNotLongEnoughSuppression.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/TapWordNotLongEnoughSuppression.java b/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/TapWordNotLongEnoughSuppression.java
new file mode 100644
index 0000000000000000000000000000000000000000..ec61c8f06aa1251f039d71a27c4ce67e1c6dfe9a
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/TapWordNotLongEnoughSuppression.java
@@ -0,0 +1,50 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.contextualsearch;
+
+import android.text.TextUtils;
+
+/**
+ * Implements the policy that a Tap on a word that's not "long enough" should be suppressed.
+ * This signal would not be reasonable to use for suppression, so we do not aggregate-log it.
+ */
+class TapWordNotLongEnoughSuppression extends ContextualSearchHeuristic {
+    private static final int WORD_NOT_LONG_ENOUGH_LENGTH = 9;
+
+    private final boolean mIsSuppressionEnabled;
+    private final boolean mIsConditionSatisfied;
+
+    /**
+     * Constructs a heuristic to determine if the current Tap is close to the edge of the word.
+     * @param contextualSearchContext The current {@link ContextualSearchContext} so we can figure
+     *        out what part of the word has been tapped.
+     */
+    TapWordNotLongEnoughSuppression(ContextualSearchContext contextualSearchContext) {
+        mIsSuppressionEnabled = ContextualSearchFieldTrial.isWordNotLongEnoughSuppressionEnabled();
+        mIsConditionSatisfied = isTapOnWordNotLongEnough(contextualSearchContext);
+    }
+
+    @Override
+    protected boolean isConditionSatisfiedAndEnabled() {
+        return mIsSuppressionEnabled && mIsConditionSatisfied;
+    }
+
+    @Override
+    protected void logResultsSeen(boolean wasSearchContentViewSeen, boolean wasActivatedByTap) {
+        if (wasActivatedByTap) {
+            ContextualSearchUma.logTapWordNotLongEnoughSeen(
+                    wasSearchContentViewSeen, mIsConditionSatisfied);
+        }
+    }
+
+    /**
+     * @return Whether the tap is on a word that's not "long enough".
+     */
+    private boolean isTapOnWordNotLongEnough(ContextualSearchContext contextualSearchContext) {
+        // If setup failed, don't suppress.
+        String tappedWord = contextualSearchContext.getTappedWord();
+        return !TextUtils.isEmpty(tappedWord) && tappedWord.length() <= WORD_NOT_LONG_ENOUGH_LENGTH;
+    }
+}