Enable HarfBuzz by default

HarfBuzz integration should be functional now, so to give it more wider
testing it is made now a required dependency on non-Windows non-Mac OSs.
By default text layout is now done by HarfBuzz but ICU LayoutEngine is
kept as a fallback and can be enabled with SAL_USE_ICULE env variable.

After 4.1.x is branched, ICU LayoutEngine should be removed completely.

Change-Id: I4fe3beeaf6092f33dd436906c11b83aeafdfbd5d

config_host/config_harfbuzz.h.in

-#ifndef CONFIG_HARFBUZZ_H
-#define CONFIG_HARFBUZZ_H
-
-#define ENABLE_HARFBUZZ 0
-
-#endif

configure.ac

@@ -720,11 +720,6 @@ AC_ARG_ENABLE(graphite,
         [Enables the compilation of Graphite smart font rendering.])
 )
 
-AC_ARG_ENABLE(harfbuzz,
-    AS_HELP_STRING([--enable-harfbuzz],
-        [Determines whether to use HarfBuzz text layout engine.])
-)
-
 AC_ARG_ENABLE(fetch-external,
     AS_HELP_STRING([--disable-fetch-external],
         [Disables fetching external tarballs from web sources.])
@@ -8482,10 +8477,9 @@ dnl ===================================================================
 dnl HarfBuzz
 dnl ===================================================================
 AC_MSG_CHECKING([whether to enable HarfBuzz support])
-if test "$_os" != "WINNT" -a "$_os" != "Darwin" && test "$enable_harfbuzz" = "" -o "$enable_harfbuzz" != "no"; then
+if test "$_os" != "WINNT" -a "$_os" != "Darwin"; then
     AC_MSG_RESULT([yes])
     ENABLE_HARFBUZZ="TRUE"
-    AC_DEFINE(ENABLE_HARFBUZZ)
     libo_CHECK_SYSTEM_MODULE([harfbuzz],[HARFBUZZ],[harfbuzz >= 0.9.10])
 else
     AC_MSG_RESULT([no])
@@ -11978,7 +11972,6 @@ AC_CONFIG_HEADERS([config_host/config_clang.h])
 AC_CONFIG_HEADERS([config_host/config_features.h])
 AC_CONFIG_HEADERS([config_host/config_global.h])
 AC_CONFIG_HEADERS([config_host/config_graphite.h])
-AC_CONFIG_HEADERS([config_host/config_harfbuzz.h])
 AC_CONFIG_HEADERS([config_host/config_lgpl.h])
 AC_CONFIG_HEADERS([config_host/config_kde4.h])
 AC_CONFIG_HEADERS([config_host/config_mingw.h])

vcl/generic/glyphs/gcach_layout.cxx

@@ -17,7 +17,6 @@
  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  */
 
-#include <config_harfbuzz.h>
 #include <gcach_ftyp.hxx>
 #include <sallayout.hxx>
 #include <salgdi.hxx>
@@ -31,10 +30,9 @@
 #include <sal/alloca.h>
 #include <rtl/instance.hxx>
 
-#if ENABLE_HARFBUZZ
 #include <harfbuzz/hb-icu.h>
 #include <harfbuzz/hb-ot.h>
-#endif
+
 #include <layout/LayoutEngine.h>
 #include <layout/LEFontInstance.h>
 #include <layout/LELanguages.h>
@@ -50,10 +48,7 @@
 ServerFontLayout::ServerFontLayout( ServerFont& rFont )
 :   mrServerFont( rFont )
 {
-    bUseHarfBuzz = false;
-#if ENABLE_HARFBUZZ
-    bUseHarfBuzz = (getenv("SAL_USE_HARFBUZZ") != NULL);
-#endif
+    bUseHarfBuzz = (getenv("SAL_USE_ICULE") == NULL);
 }
 
 void ServerFontLayout::DrawText( SalGraphics& rSalGraphics ) const
@@ -208,7 +203,6 @@ static bool needNextCode(sal_Unicode cChar)
     return lcl_CharIsJoiner(cChar) || U16_IS_TRAIL(cChar);
 }
 
-#if ENABLE_HARFBUZZ
 static hb_blob_t *getFontTable(hb_face_t* /*face*/, hb_tag_t nTableTag, void* pUserData)
 {
     char pTagName[5];
@@ -537,7 +531,6 @@ bool HbLayoutEngine::layout(ServerFontLayout& rLayout, ImplLayoutArgs& rArgs)
 
     return true;
 }
-#endif // ENABLE_HARFBUZZ
 
 // =======================================================================
 // bridge to ICU LayoutEngine
@@ -1214,12 +1207,10 @@ ServerFontLayoutEngine* ServerFont::GetLayoutEngine(bool bUseHarfBuzz)
 {
     // find best layout engine for font, platform, script and language
     if (!mpLayoutEngine) {
-#if ENABLE_HARFBUZZ
         if (bUseHarfBuzz)
             mpLayoutEngine = new HbLayoutEngine(*this);
         else
-#endif
-        mpLayoutEngine = new IcuLayoutEngine(*this);
+            mpLayoutEngine = new IcuLayoutEngine(*this);
     }
     return mpLayoutEngine;
 }