linux_aura: Enable HIDPI support

ui/base/x/x11_util.h

Index: ui/base/x/x11_util.h
diff --git a/ui/base/x/x11_util.h b/ui/base/x/x11_util.h
index bca232128cd0d2fb2e611f1d3fd028aacec31823..62aea96512c32379fa57ef06d65ef86f743c0112 100644
--- a/ui/base/x/x11_util.h
+++ b/ui/base/x/x11_util.h
@@ -309,6 +309,11 @@ UI_EXPORT void SetDefaultX11ErrorHandlers();
 // Return true if a given window is in full-screen mode.
 UI_EXPORT bool IsX11WindowFullScreen(XID window);
 
+// Returns true if a given size is in list of bogus sizes in mm that X detects
+// that should be ignored.
+UI_EXPORT bool IsXDisplaySizeBlackListed(unsigned long mm_width,
+                                         unsigned long mm_height);
+
 // Manages a piece of X11 allocated memory as a RefCountedMemory segment. This
 // object takes ownership over the passed in memory and will free it with the
 // X11 allocator when done.