[TTS] Add an override Feature for treatment of HTTP

Adds a default-disabled Feature to override the policy that Contextual
Search applies to plain HTTP pages. This allows disabling the recent
change that treats HTTP just like HTTPS landed in
https://crrev.com/c/2393526. Enabling the Feature will allow us to go
back to the legacy policy, and allow us to measure the impact of the
policy change accurately.

BUG=1124397,1129969

Change-Id: If9ceab183053a573b45a3db6051b55c625c21755
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2422264
Commit-Queue: Donn Denman <donnd@chromium.org>
Commit-Queue: Theresa  <twellington@chromium.org>
Auto-Submit: Donn Denman <donnd@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809473}

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

@@ -153,7 +153,8 @@ class ContextualSearchPolicy {
             return false;
         }
 
-        return !isUserUndecided(); // The user must have decided on privacy to resolve page content.
+        // The user must have decided on privacy to resolve page content on HTTPS.
+        return !isUserUndecided() || doesLegacyHttpPolicyApply();
     }
 
     /** @return Whether a long-press gesture can resolve. */
@@ -169,7 +170,8 @@ class ContextualSearchPolicy {
     boolean canSendSurroundings() {
         if (mDidOverrideDecidedStateForTesting) return mDecidedStateForTesting;
 
-        return !isUserUndecided(); // The user must have decided on privacy to send page content.
+        // The user must have decided on privacy to send page content on HTTPS.
+        return !isUserUndecided() || doesLegacyHttpPolicyApply();
     }
 
     /**
@@ -271,6 +273,19 @@ class ContextualSearchPolicy {
                                 ContextualSearchFieldTrial.LONGPRESS_RESOLVE_PARAM_NAME));
     }
 
+    /**
+     * Determines the policy for sending page content when on plain HTTP pages.
+     * Checks a Feature to use our legacy HTTP policy instead of treating HTTP just like HTTPS.
+     * See https://crbug.com/1129969 for details.
+     * @return whether the legacy policy for plain HTTP pages currently applies.
+     */
+    private boolean doesLegacyHttpPolicyApply() {
+        if (!isBasePageHTTP(mNetworkCommunicator.getBasePageUrl())) return false;
+
+        // Check if the legacy behavior is enabled through a feature.
+        return ChromeFeatureList.isEnabled(ChromeFeatureList.CONTEXTUAL_SEARCH_LEGACY_HTTP_POLICY);
+    }
+
     /**
      * Determines whether an error from a search term resolution request should
      * be shown to the user, or not.

chrome/browser/flags/android/chrome_feature_list.cc

@@ -142,6 +142,7 @@ const base::Feature* kFeaturesExposedToJava[] = {
     &kContextMenuSearchAndShopWithGoogleLens,
     &kContextualSearchDebug,
     &kContextualSearchDefinitions,
+    &kContextualSearchLegacyHttpPolicy,
     &kContextualSearchLongpressResolve,
     &kContextualSearchMlTapSuppression,
     &kContextualSearchSecondTap,
@@ -403,6 +404,9 @@ const base::Feature kContextualSearchDebug{"ContextualSearchDebug",
 const base::Feature kContextualSearchDefinitions{
     "ContextualSearchDefinitions", base::FEATURE_ENABLED_BY_DEFAULT};
 
+const base::Feature kContextualSearchLegacyHttpPolicy{
+    "ContextualSearchLegacyHttpPolicy", base::FEATURE_DISABLED_BY_DEFAULT};
+
 const base::Feature kContextualSearchLongpressResolve{
     "ContextualSearchLongpressResolve", base::FEATURE_DISABLED_BY_DEFAULT};
 

chrome/browser/flags/android/chrome_feature_list.h

@@ -52,6 +52,7 @@ extern const base::Feature kContextMenuSearchAndShopWithGoogleLens;
 extern const base::Feature kContentSuggestionsScrollToLoad;
 extern const base::Feature kContextualSearchDebug;
 extern const base::Feature kContextualSearchDefinitions;
+extern const base::Feature kContextualSearchLegacyHttpPolicy;
 extern const base::Feature kContextualSearchLongpressResolve;
 extern const base::Feature kContextualSearchMlTapSuppression;
 extern const base::Feature kContextualSearchSecondTap;

chrome/browser/flags/android/java/src/org/chromium/chrome/browser/flags/ChromeFeatureList.java

@@ -258,6 +258,8 @@ public abstract class ChromeFeatureList {
             "ContextMenuSearchAndShopWithGoogleLens";
     public static final String CONTEXTUAL_SEARCH_DEBUG = "ContextualSearchDebug";
     public static final String CONTEXTUAL_SEARCH_DEFINITIONS = "ContextualSearchDefinitions";
+    public static final String CONTEXTUAL_SEARCH_LEGACY_HTTP_POLICY =
+            "ContextualSearchLegacyHttpPolicy";
     public static final String CONTEXTUAL_SEARCH_ML_TAP_SUPPRESSION =
             "ContextualSearchMlTapSuppression";
     public static final String CONTEXTUAL_SEARCH_LONGPRESS_RESOLVE =

tools/metrics/histograms/enums.xml

@@ -42337,6 +42337,7 @@ from previous Chrome versions.
   <int value="-474806100" label="DataReductionProxyMainMenu:enabled"/>
   <int value="-474322576" label="disable-quick-unlock-pin"/>
   <int value="-473087416" label="DragTabsInTabletMode:enabled"/>
+  <int value="-473052940" label="ContextualSearchLegacyHttpPolicy:enabled"/>
   <int value="-472477695" label="AutofillSaveCardImprovedUserConsent:enabled"/>
   <int value="-472014137" label="HomepageTile:disabled"/>
   <int value="-472013317" label="WebRTC-H264WithOpenH264FFmpeg:disabled"/>
@@ -42622,6 +42623,7 @@ from previous Chrome versions.
       label="WebPaymentsPerMethodCanMakePaymentQuota:enabled"/>
   <int value="-174564579"
       label="ServiceWorkerImportedScriptUpdateCheck:enabled"/>
+  <int value="-174425466" label="ContextualSearchLegacyHttpPolicy:disabled"/>
   <int value="-174319545" label="BulkPrinters:enabled"/>
   <int value="-173268856" label="GesturePropertiesDBusService"/>
   <int value="-171232290" label="ListAllDisplayModes:disabled"/>