base: Quaternion::ToSting() reports normal vector and theta.

Chromium uses Quaternion for only rotation quaternion, so make it report
rotation info.

For the information, for the given rotation quaternion q,
q = (con(abs(v_theta)/2), v_theta/abs(v_theta) * sin(abs(v_theta)/2))

Change-Id: I11c574d05c621078b3b9a15ad647e9ddfe501828
Reviewed-on: https://chromium-review.googlesource.com/920749
Commit-Queue: Dongseong Hwang <dongseong.hwang@intel.com>
Reviewed-by: Dongseong Hwang <dongseong.hwang@intel.com>
Reviewed-by: Ian Vollick <vollick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553444}

CrOS-Libchrome-Original-Commit: 9f0eda6387f9da0070fc4afc3deda0a1f34cebcc
1 file changed
tree: f1ffdc302657202da14ff159f26b870b6def9176
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/