permanent, persistent and temporary modes

[Zecat]

From the spec, the drawer can be

• permanent

  Recommended default for desktop

• persistent open-, close- and togglePanel should *always* work #103

  Persistent navigation drawers are acceptable for all sizes larger than mobile.

• temporary

  Recommended for:
  Tablet
  Required for:
  Mobile

So I propose some changes on attributes :

• replace "responsiveWidth" by "tabletWidth" and "mobileWidth"
• replace "narrow" by "mobile", "tablet" and "desktop"
• remove "forceNarrow"
• add "tabletMode" and "desktopMode" ( = "permanent" | "persistent" | "temporary")

[blasten]

hmm. I would recommend taking a look at app-layout, so you can see where we are going to. https://github.com/PolymerLabs/app-layout

We'd keep this into consideration for the API design of app-drawer-layout, but I believe the code to explicitly support these modes should belong to the application rather than the element itself. In that way, the API of the element remains granular and it can support more use cases/designs.

I've moved this issue to PolymerElements/app-layout#38