Fix DoubleClickInterval and DragThreshold on aura.

views/metrics_aura.cc

Index: views/metrics_aura.cc
diff --git a/views/metrics_aura.cc b/views/metrics_aura.cc
index 46fb9b938aef472e686a6fd413c199dfdbb870ef..4eded64c63ed2ade6cfd4a34a211d876e9147e87 100644
--- a/views/metrics_aura.cc
+++ b/views/metrics_aura.cc
@@ -8,13 +8,22 @@
 #include <windows.h>
 #endif
 
+namespace {
+
+// Default double click interval in milliseconds.
+// Same as what gtk uses.
+const int kDefaultDoubleClickInterval = 500;
+
+}  // namespace
+
 namespace views {
 
 int GetDoubleClickInterval() {
 #if defined(OS_WIN)
   return ::GetDoubleClickTime();
 #else
-  return 5;
+  // TODO(jennyz): This value may need to be adjusted on different platforms.
+  return kDefaultDoubleClickInterval;
 #endif
 }