cros: Force disable stylus features on pyro.

ash/common/system/chromeos/palette/palette_utils.cc

Index: ash/common/system/chromeos/palette/palette_utils.cc
diff --git a/ash/common/system/chromeos/palette/palette_utils.cc b/ash/common/system/chromeos/palette/palette_utils.cc
index f32e40c2c1d241818618e559e1a171e39fca7768..c8c496bb3ce94c8182ef46f2672e4dbe9ec8822f 100644
--- a/ash/common/system/chromeos/palette/palette_utils.cc
+++ b/ash/common/system/chromeos/palette/palette_utils.cc
@@ -11,6 +11,7 @@
 #include "ash/common/wm_shell.h"
 #include "ash/common/wm_window.h"
 #include "base/command_line.h"
+#include "base/sys_info.h"
 #include "ui/events/devices/input_device_manager.h"
 #include "ui/events/devices/touchscreen_device.h"
 #include "ui/gfx/geometry/point.h"
@@ -18,13 +19,31 @@
 namespace ash {
 namespace palette_utils {
 
+namespace {
+// Pyro firmware currently reports it has a stylus but it does not.
+// TODO(jdufault): Remove this once firmware is fixed. See b/36367810.
+const char* kBlacklistedDevices[] = {"pyro"};
+
+bool IsBlacklisted(const std::string& name) {
+  return std::find(std::begin(kBlacklistedDevices),
+                   std::end(kBlacklistedDevices),
+                   name) != std::end(kBlacklistedDevices);
+}
+}  // namespace
+
 bool HasStylusInput() {
-  // Allow the user to force-enable by passing a switch.
+  // Allow the user to force enable or disable by passing a switch. If both are
+  // present, enabling takes precedence over disabling.
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kAshForceEnablePalette)) {
     return true;
   }
 
+  // Disable stylus for any blacklisted devices.
+  if (IsBlacklisted(base::SysInfo::GetLsbReleaseBoard()))
+    return false;
+
+  // Check to see if the hardware reports it is stylus capable.
   for (const ui::TouchscreenDevice& device :
        ui::InputDeviceManager::GetInstance()->GetTouchscreenDevices()) {
     if (device.is_stylus &&