package/qt5webkit: needs host-python

The Qt5Webkit build system hard-codes calls to 'python', but only really
supports python2.

We fix that similarly as we did in nodejs, by adding a python->python2
symlink early in the PATH when configuring/building Qt5Webkit, and
adding host-python in the dependency list.

Fixes:
    http://autobuild.buildroot.org/results/ea4/ea4dd00ee585f9f9ea1927b8b5fd9035e6733420/
    http://autobuild.buildroot.org/results/323/323ba220fae70d94c81bab9a348be844e90ace91/
    http://autobuild.buildroot.org/results/6c2/6c20c9e222f94e6b70b97b87e1393dd16da2718c/

Also slightly reorganise the dependency list, now that it no longer fits
on a single line.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/qt5/qt5webkit/qt5webkit.mk

@@ -8,7 +8,9 @@ QT5WEBKIT_VERSION = b889f460280ad98c89ede179bd3b9ce9cb02002b
 # Using GitHub since it supports downloading tarballs from random commits.
 # The http://code.qt.io/cgit/qt/qtwebkit.git/ repo doesn't allow to do so.
 QT5WEBKIT_SITE = $(call github,qtproject,qtwebkit,$(QT5WEBKIT_VERSION))
-QT5WEBKIT_DEPENDENCIES = qt5base sqlite host-ruby host-gperf host-bison host-flex
+QT5WEBKIT_DEPENDENCIES = \
+	host-bison host-flex host-gperf host-python host-ruby \
+	qt5base sqlite
 QT5WEBKIT_INSTALL_STAGING = YES
 
 QT5WEBKIT_LICENSE_FILES = Source/WebCore/LICENSE-LGPL-2 Source/WebCore/LICENSE-LGPL-2.1
@@ -31,6 +33,16 @@ ifeq ($(BR2_PACKAGE_QT5DECLARATIVE),y)
 QT5WEBKIT_DEPENDENCIES += qt5declarative
 endif
 
+# QtWebkit's build system uses python, but only supports python2. We work
+# around this by forcing python2 early in the PATH, via a python->python2
+# symlink.
+QT5WEBKIT_ENV = PATH=$(@D)/bin:$(BR_PATH)
+define QT5WEBKIT_PYTHON2_SYMLINK
+	mkdir -p $(@D)/bin
+	ln -sf $(HOST_DIR)/usr/bin/python2 $(@D)/bin/python
+endef
+QT5WEBKIT_PRE_CONFIGURE_HOOKS += QT5WEBKIT_PYTHON2_SYMLINK
+
 # Since we get the source from git, generated header files are not included.
 # qmake detects that header file generation (using the syncqt tool) must be
 # done based on the existence of a .git directory (cfr. the git_build config
@@ -39,15 +51,15 @@ endif
 # create an empty .git directory.
 define QT5WEBKIT_CONFIGURE_CMDS
 	mkdir -p $(@D)/.git
-	(cd $(@D); $(TARGET_MAKE_ENV) $(HOST_DIR)/usr/bin/qmake)
+	(cd $(@D); $(TARGET_MAKE_ENV) $(QT5WEBKIT_ENV) $(HOST_DIR)/usr/bin/qmake)
 endef
 
 define QT5WEBKIT_BUILD_CMDS
-	$(TARGET_MAKE_ENV) $(MAKE) -C $(@D)
+	$(TARGET_MAKE_ENV) $(QT5WEBKIT_ENV) $(MAKE) -C $(@D)
 endef
 
 define QT5WEBKIT_INSTALL_STAGING_CMDS
-	$(TARGET_MAKE_ENV) $(MAKE) -C $(@D) install
+	$(TARGET_MAKE_ENV) $(QT5WEBKIT_ENV) $(MAKE) -C $(@D) install
 	$(QT5_LA_PRL_FILES_FIXUP)
 endef