ibus-ui-gtk3: Enable full path of engine icon in KDE5

ibus-ui-gtk3: Enable absolute path of engine icon in KDE5

plasma-workspace 5.2 supports the icon full path.
Now the build checks if qtbase-devel is 5.4 or later since
there is no way to check the version of plasma-workspace.

BUG=https://github.com/ibus/ibus/pull/17
TEST=ui/gtk3/ibus-ui-gtk3

[Peng, 2015-03-30 16:28:24]

https://codereview.appspot.com/217310044/diff/1/check_qt_module_pri.c
File check_qt_module_pri.c (right):

https://codereview.appspot.com/217310044/diff/1/check_qt_module_pri.c#newcode23
check_qt_module_pri.c:23: #include <libgen.h>
what is this header for?

https://codereview.appspot.com/217310044/diff/1/configure.ac
File configure.ac (right):

https://codereview.appspot.com/217310044/diff/1/configure.ac#newcode594
configure.ac:594: "$CC" $CFLAGS $LDFLAGS -o check_qt_module_pri \
Can you use a shell command with grep,sed, gawk to extract the version? And then
check the version in configure.ac

[fujiwara, 2015-03-31 06:49:25]

https://codereview.appspot.com/217310044/diff/1/check_qt_module_pri.c
File check_qt_module_pri.c (right):

https://codereview.appspot.com/217310044/diff/1/check_qt_module_pri.c#newcode23
check_qt_module_pri.c:23: #include <libgen.h>
On 2015/03/30 16:28:24, Peng wrote:
> what is this header for?

for basename(3)

https://codereview.appspot.com/217310044/diff/1/configure.ac
File configure.ac (right):

https://codereview.appspot.com/217310044/diff/1/configure.ac#newcode594
configure.ac:594: "$CC" $CFLAGS $LDFLAGS -o check_qt_module_pri \
On 2015/03/30 16:28:24, Peng wrote:
> Can you use a shell command with grep,sed, gawk to extract the version? And
then
> check the version in configure.ac

Previously you said some platforms would not have sed, awk and I created the
parse program.
Done.

[Peng, 2015-03-31 15:09:46]

https://codereview.appspot.com/217310044/diff/60001/configure.ac
File configure.ac (right):

https://codereview.appspot.com/217310044/diff/60001/configure.ac#newcode587
configure.ac:587: SED=${SED:-sed}
I saw AC_PROG_GREP & AC_PROG_SEC in /usr/share/autoconf/autoconf/programs.m4

Please try use them to check those commands first.

https://codereview.appspot.com/217310044/diff/60001/configure.ac#newcode606
configure.ac:606: test $QT_GUI_MINOR_VERSION -ge 4; then
Seems you just test version of QtGui.

I tried `pkg-config Qt5Gui --modversion` in Ubuntu. It can get qt version. Can
we use it?

[fujiwara, 2015-04-01 08:34:34]

https://codereview.appspot.com/217310044/diff/60001/configure.ac
File configure.ac (right):

https://codereview.appspot.com/217310044/diff/60001/configure.ac#newcode587
configure.ac:587: SED=${SED:-sed}
On 2015/03/31 15:09:46, Peng wrote:
> I saw AC_PROG_GREP & AC_PROG_SEC in /usr/share/autoconf/autoconf/programs.m4
> 
> Please try use them to check those commands first.

Thanks.
I have noticed SED & GREP is set in linux but not in solaris. Probably the
programs.m4 didn't work.

https://codereview.appspot.com/217310044/diff/60001/configure.ac#newcode606
configure.ac:606: test $QT_GUI_MINOR_VERSION -ge 4; then
On 2015/03/31 15:09:46, Peng wrote:
> Seems you just test version of QtGui.
> 
> I tried `pkg-config Qt5Gui --modversion` in Ubuntu. It can get qt version. Can
> we use it?

Great, I could not find that pc file two weeks ago.
Done.

[Peng, 2015-04-01 20:16:14]

lgtm