make doc generation work cleanly with both qt4 & qt5

qdoc does not expand variables in include() statements, so we need to
use separate top-level "switch" files.

Change-Id: I3152baa36cb3dee055abdc68c046b445f92e1fb9
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>

doc/api/qtcreator-dev-online-qt4.qdocconf

+# Run qdoc from the directory that contains this file.
+include(../config/compat.qdocconf)
+include(qtcreator-dev-online.qdocconf)
+

doc/api/qtcreator-dev-qt4.qdocconf

+# Run qdoc from the directory that contains this file.
+include(../config/compat.qdocconf)
+include(qtcreator-dev.qdocconf)

doc/config/qtcreator-developer.qdocconf

@@ -46,7 +46,6 @@ outputdir = $OUTDIR
 exampledirs = $SRCDIR/api/examples
 indexes                 = qt.index
 
-include(compat.qdocconf)
 include(macros.qdocconf)
 include(qt-cpp-ignore.qdocconf)
 include(qt-defines.qdocconf)

doc/config/qtcreator-project.qdocconf

@@ -9,7 +9,6 @@ exampledirs = $SRCDIR/examples \
               $SRCDIR/snippets
 indexes                 = qt.index
 
-include(compat.qdocconf)
 include(macros.qdocconf)
 include(qt-cpp-ignore.qdocconf)
 include(qt-defines.qdocconf)

doc/doc.pri

 greaterThan(QT_MAJOR_VERSION, 4) {
     HELPGENERATOR = $$targetPath($$[QT_INSTALL_BINS]/qhelpgenerator) -platform minimal
     QDOC_BIN = $$targetPath($$[QT_INSTALL_BINS]/qdoc)
+    COMPAT =
 } else {
     HELPGENERATOR = $$targetPath($$[QT_INSTALL_BINS]/qhelpgenerator)
     QDOC_BIN = $$targetPath($$[QT_INSTALL_BINS]/qdoc3)
+    COMPAT = -qt4
 }
 
 
@@ -33,13 +35,13 @@ HELP_DEP_FILES = $$PWD/src/qtcreator.qdoc \
                  $$PWD/config/qt-defines.qdocconf \
                  $$PWD/config/qt-html-templates.qdocconf \
                  $$PWD/config/qt-html-default-styles.qdocconf \
-                 $$PWD/qtcreator.qdocconf
+                 $$PWD/qtcreator$${COMPAT}.qdocconf
 
-html_docs.commands = $$qdoc($$OUT_PWD/doc/html) $$PWD/qtcreator.qdocconf
+html_docs.commands = $$qdoc($$OUT_PWD/doc/html) $$PWD/qtcreator$${COMPAT}.qdocconf
 html_docs.depends += $$HELP_DEP_FILES
 html_docs.files = $$QHP_FILE
 
-html_docs_online.commands = $$qdoc($$OUT_PWD/doc/html) $$PWD/qtcreator-online.qdocconf
+html_docs_online.commands = $$qdoc($$OUT_PWD/doc/html) $$PWD/qtcreator-online$${COMPAT}.qdocconf
 html_docs_online.depends += $$HELP_DEP_FILES
 
 qch_docs.commands = $$HELPGENERATOR -o \"$$QCH_FILE\" $$QHP_FILE
@@ -59,12 +61,12 @@ DEV_HELP_DEP_FILES = \
     $$PWD/api/first-plugin.qdoc \
     $$PWD/api/plugin-specifications.qdoc \
     $$PWD/api/plugin-lifecycle.qdoc \
-    $$PWD/api/qtcreator-dev.qdocconf
+    $$PWD/api/qtcreator-dev$${COMPAT}.qdocconf
 
-dev_html_docs.commands = $$qdoc($$OUT_PWD/doc/html-dev) $$PWD/api/qtcreator-dev.qdocconf
+dev_html_docs.commands = $$qdoc($$OUT_PWD/doc/html-dev) $$PWD/api/qtcreator-dev$${COMPAT}.qdocconf
 dev_html_docs.depends += $$DEV_HELP_DEP_FILES
 
-dev_html_docs_online.commands = $$qdoc($$OUT_PWD/doc/html-dev) $$PWD/api/qtcreator-dev-online.qdocconf
+dev_html_docs_online.commands = $$qdoc($$OUT_PWD/doc/html-dev) $$PWD/api/qtcreator-dev-online$${COMPAT}.qdocconf
 dev_html_docs_online.depends += $$DEV_HELP_DEP_FILES
 
 dev_qch_docs.commands = $$HELPGENERATOR -o \"$$DEV_QCH_FILE\" $$DEV_QHP_FILE

doc/qtcreator-online-qt4.qdocconf

+# Run qdoc from the directory that contains this file.
+include(config/compat.qdocconf)
+include(qtcreator-online.qdocconf)

doc/qtcreator-qt4.qdocconf

+# Run qdoc from the directory that contains this file.
+include(config/compat.qdocconf)
+include(qtcreator.qdocconf)