build-system/gnu: Fix search path computation with implicit inputs.

Reported by Andreas Enge <andreas@enge.fr>.

* guix/build-system/gnu.scm (standard-packages): New procedure.
  (standard-inputs): Use it instead of resolving things locally.
  (gnu-build)[implicit-search-paths]: Map over (standard-packages), not
  over STANDARD-INPUTS.

Merge branch 'xorg' into core-updates

gnu: xorg: Re-enable tests for xorg-server.

* gnu/packages/xorg.scm (xorg-server): Re-enable (failing) tests.

gnu: xorg: Remove inputs already available through propagation.

* gnu/packages/xorg.scm: Remove inputs that are available through propagation.

gnu: Add xpdf.

* gnu/packages/pdf.scm (xpdf): New variable.
* gnu/packages/patches/xpdf-constchar.patch: New file.
* Makefile.am (dist_patch_DATA): Add it.

gnu: lesstif: Make package usable by adding propagated input.

* gnu/packages/lesstif.scm (lesstif): Add propagated input printproto;
     include/Xm/Print.h from lesstif includes X11/extensions/Print.h from
     printproto.

gnu: freetype: Make include file ft2build.h work without changing the CPATH
     of dependent packages.

* gnu/packages/fontutils.scm (freetype): Add link include/freetype to
     include/freetype2/freetype.

gnu: xorg: Add libxp and printproto, not included in X11R7.7.

* gnu/packages/xorg.scm (libxp, printproto): New variables.

gnu: Define `native-search-paths' for Automake, Guile, and Python.

* gnu/packages/autotools.scm (automake)[native-search-paths]: New field.
* gnu/packages/guile.scm (guile-1.8)[native-search-paths]: New field.
  (guile-2.0)[native-search-paths]: New field.
* gnu/packages/python.scm (python)[native-search-paths]: New field.

packages: Add `native-search-paths' field and honor it.

* guix/packages.scm (<search-path-specification>): New record type.
  (search-path-specification->sexp): New procedure.
  (<package>)[native-search-paths]: New field.
  (package-derivation): Accumulate the search paths, and pass them
  as #:search-paths toe BUILDER.
* guix/build-system/gnu.scm (gnu-build): Add #:search-paths.  Compute
  `implicit-search-paths'.  Pass #:search-paths in BUILDER.
* guix/build-system/perl.scm (perl-build): Add #:search-paths, pass it
  to BUILDER with the search paths of PERL.
* guix/build-system/cmake.scm (cmake-build): Add #:search-paths, pass it
  to BUILDER.
* guix/build-system/trivial.scm (trivial-build): Add #:search-paths,
  ignore it.
* guix/build/gnu-build-system.scm (set-paths): Add #:search-paths.
  Remove explicit settings of CPATH, LIBRARY_PATH, and PKG_CONFIG_PATH.
  Instead, walk SEARCH-PATHS and call `set-path-environment-variable'
  for them.
* guix/build/perl-build-system.scm (perl-build): Remove PERL5LIB setting.
* tests/packages.scm ("search paths"): New test.
* gnu/packages/bootstrap.scm (%bootstrap-guile)[raw]: Add
  #:search-paths.
  (%bootstrap-gcc): Add `native-search-paths' field.
* gnu/packages/perl.scm (perl): Likewise.
* gnu/packages/pkg-config.scm (pkg-config): Likewise.
* gnu/packages/glib.scm (intltool): Remove `arguments'.
* gnu/packages/avahi.scm (avahi): Remove #:phases.

build: Pass the appropriate flags when building `libstore.a'.

* daemon.am (libstore_a_CFLAGS): Rename to...
  (libstore_a_CXXFLAGS): ... this.

build-system/gnu: Remove #:path-exclusions parameter.

* guix/build/gnu-build-system.scm (set-paths): Remove `path-exclusions'
  parameter.  Replace `relevant-input-directories' by
  `input-directories'.
* guix/build-system/gnu.scm (gnu-build): Remove `path-exclusions'
  parameter; don't pass it in BUILDER.
* guix/build-system/cmake.scm (cmake-build): Likewise.

gnu: xorg: Make font-adobe75dpi and font-adobe100dpi compile (not install).

* gnu/packages/xorg/scm (font-adobe75dpi, font-adobe100dpi): Add inputs
     bdftopcf, font-util and mkfontdir.

gnu: xorg: Add mtdev and make xf86-input-synaptics compile (not install).

* gnu/packages/xorg.scm (mtdev): New variable.
* gnu/packages/xorg.scm (xf86-input-synaptics): Add inputs libx11, libxi
     and mtdev.
* gnu/packages/xorg.scm (libxi): Propagate input libxext.

gnu: xorg: Disable not compiling xf86-video-geode.

* gnu/packages/xorg.scm (xf86-video-geode): Comment out since not compiling
     (assembler errors).

gnu: xorg: Fix compilation of xorg-server.

* gnu/packages/xorg.scm (mesa): Propagate input libxxf86vm.

gnu: xorg: Disable xf86-video-glide.

* gnu/packages/xorg.scm (xf86-video-glide): Comment variable; driver for
     obsolete graphics cards, depends on libglide, last updated in 2003,
     and which does not compile out of the box any more.

gnu: xorg: Disable xf86-video-wsfb.

* gnu/packages/xorg.scm (xf86-video-wsfb): Comment variable, only relevant
     for the frame buffer on BSD systems.

gnu: xorg: Make xgamma compile.

* gnu/packages/xorg.scm (libxxf86vm): Propagate inputs libxext and
     xf86vidmodeproto.

gnu: xorg: Make xvinfo compile.

* gnu/packages/xorg.scm (libxv): Propagate input videoproto.