stage: Fix indentation in pick methods

https://bugzilla.gnome.org/show_bug.cgi?id=712563
Signed-off-by: Emmanuele Bassi <ebassi@gnome.org>
stage: Remove the pick buffer caching

Since the journal is flushed on context switches, trying to use a cached
buffer means that we will use glReadPixels when picking, which isn't what
we want. Instead, always use a clipped draw, and remove the logic for
caching the pick buffer.

https://bugzilla.gnome.org/show_bug.cgi?id=712563
(cherry picked from commit a427c120c239a471024375277d5e03e9b8863835)
Signed-off-by: Emmanuele Bassi <ebassi@gnome.org>
ClutterStage: Don't add empty actors to the stage clip

Currently, if an actor with an empty paint volume is queued for redraw, it
will union in the box +0+0x1x1 to the stage clip bounds - avoid that
by special casing empty paint volumes.

https://bugzilla.gnome.org/show_bug.cgi?id=719747
(cherry picked from commit a2551dfa602f938b168fdf23fb4d2fcef4f1d892)
Signed-off-by: Emmanuele Bassi <ebassi@gnome.org>
gesture-action: fix memory corruption

abcf1d589f29ba7914d5648bb9814ad26c13cd83 introduced a crasher because
the 'point' variable points to a piece of memory that is being
reallocated by the begin_gesture (by a g_array_set_size) call 5 lines
before.

https://bugzilla.gnome.org/show_bug.cgi?id=710227
(cherry picked from commit 97724939c8de004d7fa230f3ff64862d957f93a9)
Signed-off-by: Emmanuele Bassi <ebassi@gnome.org>
text: Fix the implementation of delete_chars()

The internal delete_text() implementation takes a start and an end
position, whereas the public delete_chars() method takes a number of
characters to delete starting from the current cursor position.

(cherry picked from commit 0dc4986f666edb067f43f328756df9103d840086)
Signed-off-by: Emmanuele Bassi <ebassi@gnome.org>
Release Clutter 1.16.4
Post-release version bump to 1.16.5