Fix fallbacks for adapted common script

When the platform plugin gives us specific fallbacks for a
specific script, we need to respect this, and load the correct
font family regardless of which writing systems it supports.

This is especially important since the common script is adapted
to match surrounding, proper scripts, so characters such as
digits next to e.g. Hebrew text will be marked as Hebrew. On
stock Android, there is a single Hebrew font, and this would
previously be put in all fallback slots for Hebrew regardless of
what fallback fonts were dictated by the platform plugin. Since
this font does not support the digits, they would show up as boxes.

[ChangeLog][Android] Fixed common characters like digits and
punctuation showing as boxes when positioned next to non-latin
scripts.

Task-number: QTBUG-39377
Change-Id: I1555e208a8ddc587c0bbdbfff1600cafdd9442e9
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Fix fallbacks for adapted common script

When the platform plugin gives us specific fallbacks for a
specific script, we need to respect this, and load the correct
font family regardless of which writing systems it supports.

This is especially important since the common script is adapted
to match surrounding, proper scripts, so characters such as
digits next to e.g. Hebrew text will be marked as Hebrew. On
stock Android, there is a single Hebrew font, and this would
previously be put in all fallback slots for Hebrew regardless of
what fallback fonts were dictated by the platform plugin. Since
this font does not support the digits, they would show up as boxes.

[ChangeLog][Android] Fixed common characters like digits and
punctuation showing as boxes when positioned next to non-latin
scripts.

Task-number: QTBUG-39377
Change-Id: I1555e208a8ddc587c0bbdbfff1600cafdd9442e9
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Android: enable FBO readback workaround for more devices.

Now enabled for all devices equipped with a GPU from the Mali-4xx
series or Adreno 2xx series.

Task-number: QTBUG-40131
Change-Id: I2923c07033ef768aceec6f5590dbb6f26aa67087
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Fixed wrong function name in a file snippet

Change-Id: I453c5085685badeb6577009a0c6935dfe384258f
Reviewed-by: Richard J. Moore <rich@kde.org>
Android: Prefer "Droid Serif" as default serif font

I've also updated the qfont test so it passes on Android now. Note that
there are no suitable cursive/fantasy fonts on Android, so the regular
default "Roboto" (or "Droid Sans" on older devices) will be picked here
instead.

[ChangeLog][Android] Fixed font selection to prefer "Droid Serif" when
Serif style hint is set on QFont.

Change-Id: I294eebcc4d79410e435bdddce552acc6044753b2
Reviewed-by: Christian Stromme <christian.stromme@digia.com>