Add UA compatible meta tag in bootstrap handler

[denis-anisimov]

Fix for #2477

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This change is 

[torok-peter]

Reviewed 2 of 2 files at r1.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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flow-server/src/test/java/com/vaadin/server/BootstrapHandlerTest.java, line 162 at r1 (raw file):

    @Test
    public void headHasmetaTags() throws Exception {

headHasMetaTags ?

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Comments from Reviewable

[denis-anisimov]

Review status: 1 of 2 files reviewed at latest revision, 1 unresolved discussion.

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flow-server/src/test/java/com/vaadin/server/BootstrapHandlerTest.java, line 162 at r1 (raw file):

Previously, torok-peter (Péter Török) wrote…

headHasMetaTags ?

Done.

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Comments from Reviewable

[torok-peter]

Reviewed 1 of 1 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable

[denis-anisimov]

Reviewed 2 of 2 files at r3.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable