Initialize device scale factor correctly on Android

ui/gfx/display.cc

Index: ui/gfx/display.cc
diff --git a/ui/gfx/display.cc b/ui/gfx/display.cc
index e647f650603ff777e9a2c46931e5e11c7d3c645a..d47f8deffca2dbe3782c81d226ced61e0d112389 100644
--- a/ui/gfx/display.cc
+++ b/ui/gfx/display.cc
@@ -83,8 +83,15 @@ void Display::SetScaleAndBounds(
     float device_scale_factor,
     const gfx::Rect& bounds_in_pixel) {
   Insets insets = bounds_.InsetsFrom(work_area_);
-  if (!HasForceDeviceScaleFactor())
+  if (!HasForceDeviceScaleFactor()) {
+#if defined(OS_CHROMEOS) || defined(OS_MACOSX)
+    // Unless an explicit scale factor was provided for testing, ensure the
+    // scale is integral.
+    device_scale_factor = static_cast<int>(device_scale_factor);
+#endif
     device_scale_factor_ = device_scale_factor;
+  }
+  device_scale_factor_ = std::max(1.0f, device_scale_factor_);

[oshima, 2012/11/14 16:52:35]

Is this necessary for android?
I most likely eliminate these safe guard in near future, and want to know if
I should do it only for chromeos, or can just eliminate for all platforms.

[johnme, 2012/11/14 16:56:45]

There should never be any harm in using this safeguard (as device_scale_factor_
should never be less than 1). So I'd recommend just keeping it for all
platforms.

 #if defined(USE_AURA)
   bounds_in_pixel_ = bounds_in_pixel;
 #endif