[ios] Remove unused viewport adjustment experiments

Code does not use these experiment enums anymore. Only kSmoothScrollingDefault
is used to determine how to adjust the viewport insets.

Bug: 914042
Change-Id: I71c4112d7f2f820a4793d74d0c5a0726513f300a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1812121Reviewed-by: Kurt Horimoto <kkhorimoto@chromium.org>
Commit-Queue: Chris Lu <thegreenfrog@chromium.org>
Cr-Commit-Position: refs/heads/master@{#699980}

ios/chrome/browser/flags/about_flags.mm

@@ -323,11 +323,9 @@ const flags_ui::FeatureEntry kFeatureEntries[] = {
      flags_ui::kOsIos,
      FEATURE_VALUE_TYPE(autofill::features::kAutofillRichMetadataQueries)},
     {"fullscreen-viewport-adjustment-experiment",
-     flag_descriptions::kFullscreenViewportAdjustmentExperimentName,
-     flag_descriptions::kFullscreenViewportAdjustmentExperimentDescription,
-     flags_ui::kOsIos,
-     MULTI_VALUE_TYPE(
-         fullscreen::features::kViewportAdjustmentExperimentChoices)},
+     flag_descriptions::kFullscreenSmoothScrollingName,
+     flag_descriptions::kFullscreenSmoothScrollingDescription, flags_ui::kOsIos,
+     FEATURE_VALUE_TYPE(fullscreen::features::kSmoothScrollingDefault)},
     {"autofill-enforce-min-required-fields-for-heuristics",
      flag_descriptions::kAutofillEnforceMinRequiredFieldsForHeuristicsName,
      flag_descriptions::

ios/chrome/browser/flags/ios_chrome_flag_descriptions.cc

@@ -204,11 +204,10 @@ const char kFindInPageiFrameName[] = "Find in Page in iFrames.";
 const char kFindInPageiFrameDescription[] =
     "When enabled, Find In Page will search in iFrames.";
 
-const char kFullscreenViewportAdjustmentExperimentName[] =
-    "Fullscreen Viewport Adjustment Mode";
-const char kFullscreenViewportAdjustmentExperimentDescription[] =
-    "The different ways in which the web view's viewport is updated for scroll "
-    "events.  The default option updates the web view's frame.";
+const char kFullscreenSmoothScrollingName[] = "Fullscreen Smooth Scrolling";
+const char kFullscreenSmoothScrollingDescription[] =
+    "When enabled, the web view's insets are updated for scoll events. If "
+    "disabled, the the web view's frame are updated.";
 
 const char kIgnoresViewportScaleLimitsName[] = "Ignore Viewport Scale Limits";
 const char kIgnoresViewportScaleLimitsDescription[] =

ios/chrome/browser/flags/ios_chrome_flag_descriptions.h

@@ -169,8 +169,8 @@ extern const char kFindInPageiFrameDescription[];
 
 // Title and description for the command line switch used to determine the
 // active fullscreen viewport adjustment mode.
-extern const char kFullscreenViewportAdjustmentExperimentName[];
-extern const char kFullscreenViewportAdjustmentExperimentDescription[];
+extern const char kFullscreenSmoothScrollingName[];
+extern const char kFullscreenSmoothScrollingDescription[];
 
 // Title and description for the flag to ignore viewport scale limits.
 extern const char kIgnoresViewportScaleLimitsName[];

ios/chrome/browser/ui/fullscreen/fullscreen_features.h

@@ -11,37 +11,10 @@
 namespace fullscreen {
 namespace features {
 
-// The name of the command line switch used to control the method by which the
-// viewport of the content area is updated by scrolling events.
-extern const char kViewportAdjustmentExperimentCommandLineSwitch[];
-
-// The available viewport adjustment experiments.  The choices in this array
-// correspond with the ViewportAdjustmentExperiment values.
-extern const flags_ui::FeatureEntry::Choice
-    kViewportAdjustmentExperimentChoices[6];
-
 // Feature used by finch config to enable smooth scrolling when the default
 // viewport adjustment experiment is selected via command line switches.
 extern const base::Feature kSmoothScrollingDefault;
 
-// Enum type describing viewport adjustment experiments.
-enum class ViewportAdjustmentExperiment : short {
-  FRAME = 0,      // Adjust the viewport by resizing the entire WKWebView.
-  CONTENT_INSET,  // Adjust the viewport by updating the WKWebView's scroll view
-                  // contentInset.
-  SAFE_AREA,  // Adjust the viewport by updating the safe area of the browser
-              // container view.
-  HYBRID,  // Translates the web view up and down and updates the viewport using
-           // safe area insets.
-  SMOOTH_SCROLLING,  // Adjusts the viewport using the smooth scrolling
-                     // workaround.
-};
-
-// Convenience method for retrieving the active viewport adjustment experiment
-// from the command line. TODO(crbug.com/914042): Remove once the internal
-// references are moved to ShouldUseSmoothScrolling().
-ViewportAdjustmentExperiment GetActiveViewportExperiment();
-
 // Convenience method for determining when to adjust the viewport by resizing
 // WKWebView or using smooth scrolling.
 bool ShouldUseSmoothScrolling();

ios/chrome/browser/ui/fullscreen/fullscreen_features.mm

@@ -11,59 +11,12 @@
 #error "This file requires ARC support."
 #endif
 
-namespace {
-// The command line values for the content inset and safe area experiment
-// choices.
-const char kFrameChoiceValue[] = "frame";
-const char kContentInsetChoiceValue[] = "content-inset";
-const char kSafeAreaChoiceValue[] = "safe-area";
-const char kHybridChoiceValue[] = "hybrid";
-const char kSmoothScrollingChoiceValue[] = "smooth";
-}
-
 namespace fullscreen {
 namespace features {
 
-const char kViewportAdjustmentExperimentCommandLineSwitch[] =
-    "fullscreen-viewport-adjustment-experiment";
-
-const flags_ui::FeatureEntry::Choice kViewportAdjustmentExperimentChoices[] = {
-    {flags_ui::kGenericExperimentChoiceDefault, "", ""},
-    {"Update Content Inset", kViewportAdjustmentExperimentCommandLineSwitch,
-     "content-inset"},
-    {"Update Safe Area", kViewportAdjustmentExperimentCommandLineSwitch,
-     "safe-area"},
-    {"Use Hybrid Implementation",
-     kViewportAdjustmentExperimentCommandLineSwitch, "hybrid"},
-    {"Use Smooth Scrolling", kViewportAdjustmentExperimentCommandLineSwitch,
-     "smooth"},
-    {"Update Frame", kViewportAdjustmentExperimentCommandLineSwitch, "frame"}};
-
 const base::Feature kSmoothScrollingDefault{"FullscreenSmoothScrollingDefault",
                                             base::FEATURE_ENABLED_BY_DEFAULT};
 
-ViewportAdjustmentExperiment GetActiveViewportExperiment() {
-  const base::CommandLine* command_line =
-      base::CommandLine::ForCurrentProcess();
-  if (command_line->HasSwitch(kViewportAdjustmentExperimentCommandLineSwitch)) {
-    std::string viewport_experiment = command_line->GetSwitchValueASCII(
-        kViewportAdjustmentExperimentCommandLineSwitch);
-    if (viewport_experiment == std::string(kContentInsetChoiceValue))
-      return ViewportAdjustmentExperiment::CONTENT_INSET;
-    if (viewport_experiment == std::string(kSafeAreaChoiceValue))
-      return ViewportAdjustmentExperiment::SAFE_AREA;
-    if (viewport_experiment == std::string(kHybridChoiceValue))
-      return ViewportAdjustmentExperiment::HYBRID;
-    if (viewport_experiment == std::string(kSmoothScrollingChoiceValue))
-      return ViewportAdjustmentExperiment::SMOOTH_SCROLLING;
-    if (viewport_experiment == std::string(kFrameChoiceValue))
-      return ViewportAdjustmentExperiment::FRAME;
-  }
-  return base::FeatureList::IsEnabled(kSmoothScrollingDefault)
-             ? ViewportAdjustmentExperiment::SMOOTH_SCROLLING
-             : ViewportAdjustmentExperiment::FRAME;
-}
-
 bool ShouldUseSmoothScrolling() {
   return base::FeatureList::IsEnabled(kSmoothScrollingDefault);
 }