Extract title/description to vaadin-login-overlay

[DiegoCardoso]

• Make vaadin-login-overlay-element extend vaadin-overlay template
• Move title/description to vaadin-login-overlay
• Remove props from mixin
• Pass through to vloe props set on vaadin-login-overlay
• Move styles to vaadin-login-overlary-element
• Move tests related to title/description

Fix #45

---

This change is 

[coveralls]

Pull Request Test Coverage Report for Build 185

• 19 of 19 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.4%) to 97.087%

---

Totals
Change from base Build 183:	0.4%
Covered Lines:	71
Relevant Lines:	71

---

💛 - Coveralls

[tulioag]

Great work, thanks.

I only found a few issues with the demos:

• I18n demo looks ugly. Can we apply the same styles as in the "Basic" version?
• Should we add a demo with the overlay without full screen? I think it looks much better with the overlay and the full screen version is hidden by default.
• Full screen demo does not work in IE11.

Reviewed 8 of 8 files at r1.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @DiegoCardoso)

---

test/login-test.html, line 108 at r1 (raw file):

        login.i18n = i18n;
        expect(additionalInformation.textContent).to.be.equal(login.i18n.additionalInformation);
        // expect(login.title).to.be.equal(login.i18n.additionalInformation);

Can we remove the commented out code?

[tulioag]

Reviewed 3 of 3 files at r2.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @DiegoCardoso)

[DiegoCardoso]

Reviewable status: 8 of 9 files reviewed, 1 unresolved discussion (waiting on @tulioag)

---

test/login-test.html, line 108 at r1 (raw file):

Previously, tulioag (Tulio Garcia) wrote…

Can we remove the commented out code?

Done.

[tulioag]

Reviewed 2 of 2 files at r3.
Reviewable status: complete! all files reviewed, all discussions resolved

[tulioag]

Reviewed 3 of 3 files at r4.
Reviewable status: all files reviewed, 4 unresolved discussions (waiting on @web-padawan)

[tulioag]

Reviewable status: all files reviewed, 4 unresolved discussions (waiting on @web-padawan)

[DiegoCardoso]

Reviewed 4 of 4 files at r5.
Dismissed @web-padawan from 3 discussions.
Reviewable status: complete! all files reviewed, all discussions resolved