Omnibox UI Experiments: Add vertical margin variations to about:flags

chrome/browser/ui/views/omnibox/omnibox_result_view.cc

 // Copyright (c) 2012 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.
 
 // For WinDDK ATL compatibility, these ATL headers must come first.
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <atlbase.h>  // NOLINT
 #include <atlwin.h>  // NOLINT
 #endif
 
 #include "base/macros.h"
 #include "chrome/browser/ui/views/omnibox/omnibox_result_view.h"
 
 #include <limits.h>
 
 #include <algorithm>  // NOLINT
 
 #include "base/i18n/bidi_line_iterator.h"
+#include "base/metrics/field_trial_params.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "chrome/browser/ui/layout_constants.h"
 #include "chrome/browser/ui/views/location_bar/background_with_1_px_border.h"
 #include "chrome/browser/ui/views/location_bar/location_bar_view.h"
 #include "chrome/browser/ui/views/omnibox/omnibox_popup_contents_view.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/grit/components_scaled_resources.h"
+#include "components/omnibox/browser/omnibox_field_trial.h"
 #include "components/omnibox/browser/omnibox_popup_model.h"
 #include "components/omnibox/browser/vector_icons.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/accessibility/ax_node_data.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/material_design/material_design_controller.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/theme_provider.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/color_palette.h"
@@ skipping 678 matching lines @@
   description_rendertext_->SetDisplayRect(gfx::Rect(text_bounds_.width(), 0));
   description_rendertext_->GetStringSize();
   return GetAnswerFont().GetHeight() * description_rendertext_->GetNumLines();
 }
 
 int OmniboxResultView::GetVerticalMargin() const {
   // Regardless of the text size, we ensure a minimum size for the content line
   // here. This minimum is larger for hybrid mouse/touch devices to ensure an
   // adequately sized touch target.
   using Md = ui::MaterialDesignController;
-  const int kIconVerticalPad = Md::GetMode() == Md::MATERIAL_HYBRID ? 8 : 4;
+  const int kIconVerticalPad = base::GetFieldTrialParamByFeatureAsInt(
+      omnibox::kUIExperiments,
+      OmniboxFieldTrial::kUIExperimentsVerticalMarginParam,
+      Md::GetMode() == Md::MATERIAL_HYBRID ? 8 : 4);
   const int min_height = LocationBarView::kIconWidth + 2 * kIconVerticalPad;
 
   return std::max(kVerticalPadding, (min_height - GetTextHeight()) / 2);
 }
 
 std::unique_ptr<gfx::RenderText> OmniboxResultView::CreateAnswerText(
     const SuggestionAnswer::ImageLine& line,
     const gfx::FontList& font_list) const {
   std::unique_ptr<gfx::RenderText> destination =
       CreateRenderText(base::string16());
@@ skipping 64 matching lines @@
   destination->AppendText(text);
   const TextStyle& text_style = GetTextStyle(text_type);
   // TODO(dschuyler): follow up on the problem of different font sizes within
   // one RenderText.  Maybe with destination->SetFontList(...).
   destination->ApplyWeight(
       is_bold ? gfx::Font::Weight::BOLD : gfx::Font::Weight::NORMAL, range);
   destination->ApplyColor(
       GetNativeTheme()->GetSystemColor(text_style.colors[GetState()]), range);
   destination->ApplyBaselineStyle(text_style.baseline, range);
 }