support ICU as Qt4 does

Signed-off-by: Ivailo Monev <xakepa10@gmail.com>

CMakeLists.txt

@@ -82,6 +82,9 @@ add_feature_info(fontconfig WITH_FONTCONFIG "an open source something")
 option(WITH_FREETYPE "Build freetype2 support" ON)
 add_feature_info(freetype2 WITH_FREETYPE "an open source something")
 
+option(WITH_ICU "Build icu support" ON)
+add_feature_info(icu WITH_ICU "an open source something")
+
 # TODO: enable when building against external harfbuzz works
 option(WITH_HARFBUZZ "Build harfbuzz support" OFF)
 add_feature_info(harfbuzz WITH_HARFBUZZ "an open source something")
@@ -297,6 +300,14 @@ set_package_properties(Freetype PROPERTIES
     TYPE RECOMMENDED
 )
 
+find_package(ICU)
+set_package_properties(ICU PROPERTIES
+    PURPOSE "ICU locales support"
+    DESCRIPTION "Mature, widely used libraries providing Unicode and Globalization support"
+    URL "http://site.icu-project.org/"
+    TYPE RECOMMENDED
+)
+
 # currently unused
 find_package(HarfBuzz)
 set_package_properties(HarfBuzz PROPERTIES

cmake/modules/FindICU.cmake

@@ -0,0 +1,39 @@
+# - Try to find International Components for Unicode
+# Once done this will define
+#
+#  ICU_FOUND - system has ICU
+#  ICU_INCLUDES - the ICU include directory
+#  ICU_LIBRARIES - The libraries needed to use ICU
+#
+# Copyright (c) 2015, Ivailo Monev, <xakepa10@gmail.com>
+#
+# Redistribution and use is allowed according to the terms of the BSD license.
+
+if(ICU_INCLUDES AND ICU_LIBRARIES)
+    set(ICU_FIND_QUIETLY TRUE)
+endif()
+
+find_path(ICU_INCLUDES
+    NAMES
+    unistr.h
+    PATH_SUFFIXES unicode
+    HINTS
+    $ENV{ICUDIR}/include
+    /usr/include
+    /usr/local/include
+    ${INCLUDE_INSTALL_DIR}
+)
+
+find_library(ICU_LIBRARIES
+    icui18n
+    HINTS
+    $ENV{ICUDIR}/lib
+    /usr/lib
+    /usr/local/lib
+    ${LIB_INSTALL_DIR}
+)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(ICU DEFAULT_MSG ICU_INCLUDES ICU_LIBRARIES)
+
+mark_as_advanced(ICU_INCLUDES ICU_LIBRARIES)

src/core/tools/tools.cmake

@@ -133,8 +133,7 @@ else()
     )
 endif()
 
-# TODO: look for ICU package
-if(ICU_FOUND)
+if(WITH_ICU AND ICU_FOUND)
     set(CORE_SOURCES
         ${CORE_SOURCES}
         ${CMAKE_CURRENT_SOURCE_DIR}/tools/qlocale_icu.cpp