Clean up some nits in ash/touch/touchscreen_util.cc.

ash/touch/touchscreen_util.cc

 // Copyright 2014 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.
 
 #include "ash/touch/touchscreen_util.h"
 
 #include <set>
 
 #include "base/files/file_util.h"
 #include "base/logging.h"
@@ skipping 12 matching lines @@
                const ui::TouchscreenDevice* device) {
   display->AddInputDevice(device->id);
   display->set_touch_support(display::Display::TOUCH_SUPPORT_AVAILABLE);
 }
 
 // Returns true if |path| is likely a USB device.
 bool IsDeviceConnectedViaUsb(const base::FilePath& path) {
   std::vector<base::FilePath::StringType> components;
   path.GetComponents(&components);
 
-  for (base::FilePath::StringType component : components) {
+  for (const auto& component : components) {
     if (base::StartsWith(component, "usb",
                          base::CompareCase::INSENSITIVE_ASCII))
       return true;
   }
 
   return false;
 }
 
 // Returns the UDL association score between |display| and |device|. A score <=
 // 0 means that there is no association.
-int GetUdlAssociationScore(display::ManagedDisplayInfo* display,
+int GetUdlAssociationScore(const display::ManagedDisplayInfo* display,
                            const ui::TouchscreenDevice* device) {
   // If the devices are not both connected via USB, then there cannot be a UDL
   // association score.
   if (!IsDeviceConnectedViaUsb(display->sys_path()) ||
       !IsDeviceConnectedViaUsb(device->sys_path))
     return 0;
 
   // The association score is simply the number of prefix path components that
   // sysfs paths have in common.
   std::vector<base::FilePath::StringType> display_components;
   std::vector<base::FilePath::StringType> device_components;
   display->sys_path().GetComponents(&display_components);
   device->sys_path.GetComponents(&device_components);
 
   std::size_t largest_idx = 0;
   while (largest_idx < display_components.size() &&
          largest_idx < device_components.size() &&
          display_components[largest_idx] == device_components[largest_idx]) {
     ++largest_idx;
   }
   return largest_idx;
 }
 
 // Tries to find a UDL device that best matches |display|. Returns nullptr
 // if one is not found.
 const ui::TouchscreenDevice* GuessBestUdlDevice(
-    display::ManagedDisplayInfo* display,
+    const display::ManagedDisplayInfo* display,
     const DeviceList& devices) {
   int best_score = 0;
   const ui::TouchscreenDevice* best_device = nullptr;
 
   for (const ui::TouchscreenDevice* device : devices) {
     int score = GetUdlAssociationScore(display, device);
     if (score > best_score) {
       best_score = score;
       best_device = device;
     }
@@ skipping 21 matching lines @@
       devices->erase(std::find(devices->begin(), devices->end(), device));
 
       continue;
     }
 
     ++display_it;
   }
 }
 
 // Returns true if |display| is internal.
-bool IsInternalDisplay(display::ManagedDisplayInfo* display) {
+bool IsInternalDisplay(const display::ManagedDisplayInfo* display) {
   return display::Display::IsInternalDisplayId(display->id());
 }
 
 // Returns true if |device| is internal.
 bool IsInternalDevice(const ui::TouchscreenDevice* device) {
   return device->type == ui::InputDeviceType::INPUT_DEVICE_INTERNAL;
 }
 
 void AssociateInternalDevices(DisplayInfoList* displays, DeviceList* devices) {
   VLOG(2) << "Trying to match internal devices (" << displays->size()
@@ skipping 87 matching lines @@
 }
 
 void AssociateToSingleDisplay(DisplayInfoList* displays, DeviceList* devices) {
   // If there is only one display left, then we should associate all input
   // devices with it.
 
   VLOG(2) << "Trying to match to single display (" << displays->size()
           << " displays and " << devices->size() << " devices to match)";
 
   // We only associate to one display.
-  if (displays->size() != 1 || devices->size() == 0)
+  if (displays->size() != 1 || devices->empty())
     return;
 
   display::ManagedDisplayInfo* display = *displays->begin();
   for (const ui::TouchscreenDevice* device : *devices) {
     VLOG(2) << "=> Matched device " << device->name << " to display "
             << display->name();
     Associate(display, device);
   }
 
   displays->clear();
@@ skipping 43 matching lines @@
   AssociateSameSizeDevices(&displays, &devices);
   AssociateToSingleDisplay(&displays, &devices);
 
   for (const display::ManagedDisplayInfo* display : displays)
     LOG(WARNING) << "Unmatched display " << display->name();
   for (const ui::TouchscreenDevice* device : devices)
     LOG(WARNING) << "Unmatched device " << device->name;
 }
 
 }  // namespace ash