[geary] Bump minimum library and vala version reqirements.

[Michael Gratton <mjog src gnome org>]

commit 1e1b0800a1ff50443cc4321ebd31df79298021b2
Author: Michael James Gratton <mike vee net>
Date:   Wed Oct 4 17:33:25 2017 +1100

    Bump minimum library and vala version reqirements.
    
    * CMakeLists.txt: GTK+ to 3.22, WebKitGTK to 2.16.
    
    * src/CMakeLists.txt: Vala to 0.34.

 CMakeLists.txt     |    6 +++---
 src/CMakeLists.txt |    2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4f15fb6..3199468 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,9 +27,9 @@ set(LANGUAGE_SUPPORT_DIRECTORY ${CMAKE_INSTALL_PREFIX}/share/locale)
 # Primary library minimum version requirements. See src/CMakeLists.txt
 # for others.
 #
-set(TARGET_GLIB 2.42) # Also passed to valac, so don't include a point rev
-set(TARGET_GTK 3.14.0)
-set(TARGET_WEBKIT 2.10)
+set(TARGET_GLIB 2.50) # Also passed to valac, so don't include a point rev
+set(TARGET_GTK 3.22.0)
+set(TARGET_WEBKIT 2.16)
 
 if (NOT ISO_CODE_639_XML)
   find_path(ISOCODES_DIRECTORY NAMES iso_639.xml PATHS ${CMAKE_INSTALL_PREFIX} /usr/share/xml/iso-codes)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 1e4213f..2b877de 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -427,7 +427,7 @@ mailer/main.vala
 # Vala
 find_package(Vala REQUIRED)
 include(ValaVersion)
-ensure_vala_version("0.26.0" MINIMUM)
+ensure_vala_version("0.34.0" MINIMUM)
 include(ValaPrecompile)
 
 # Vapigen