Centralize place where we ensure qdoc is built before generating docs

Change-Id: Ie0220d3c76990f6052edcd8c738e4e2807f35c71
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>

src/tools/bootstrap/bootstrap.pro

@@ -130,9 +130,6 @@ freeze_target.target = freeze
 freeze_target.commands =
 freeze_target.depends = first
 QMAKE_EXTRA_TARGETS += freeze_target
-docs.commands =
-docs.depends = first
-QMAKE_EXTRA_TARGETS += docs
 
 # We need the forwarding headers before their respective modules are built,
 # so do a minimal syncqt run.

src/tools/qdoc/qdoc.pro

@@ -124,9 +124,4 @@ QMAKE_EXTRA_TARGETS += html-docs qch-docs
 target.path = $$[QT_HOST_BINS]
 INSTALLS += target
 
-# Ensure that qdoc is built before we generate the docs
-docs.commands =
-docs.depends = first
-QMAKE_EXTRA_TARGET += docs
-
 load(qt_targets)

src/tools/tools.pro

@@ -34,3 +34,10 @@ contains(QT_CONFIG, dbus) {
 }
 
 SUBDIRS = $$TOOLS_SUBDIRS
+
+# Ensure qdoc is built before making any docs. We rely on the existing dependency
+# on bootstrap for each of the other tools to ensure they also build qdoc first,
+# and likewise, the dependency of the rest of the build on tools, src, etc.
+bootstrap_docs.depends += $${src_tools_qdoc.target}-make_first
+bootstrap_docs.target = $${src_tools_bootstrap.target}-docs
+QMAKE_EXTRA_TARGETS += bootstrap_docs