gtest: retrieve package from github

https://googletest.googlecode.com/files is no more available, so update
gtest.mk and gtest.hash to retrieve googletest source code as a tar.gz
(and not a zip) from github as https://googletest.googlecode.com is now
a redirection to https://github.com/google/googletest.

Signed-off-by: Fabrice Fontaine <fabrice.fontaine@orange.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/gtest/gtest.hash

@@ -1,2 +1,2 @@
-# From http://code.google.com/p/googletest/downloads/detail?name=gtest-1.7.0.zip&can=2&q=
-sha1	f85f6d2481e2c6c4a18539e391aa4ea8ab0394af	gtest-1.7.0.zip
+# Locally computed:
+sha256	f73a6546fdf9fce9ff93a5015e0333a8af3062a152a9ad6bcb772c96687016cc	gtest-release-1.7.0.tar.gz

package/gtest/gtest.mk

@@ -5,9 +5,8 @@
 ################################################################################
 
 # Make sure this remains the same version as the gmock one
-GTEST_VERSION = 1.7.0
-GTEST_SOURCE = gtest-$(GTEST_VERSION).zip
-GTEST_SITE = http://googletest.googlecode.com/files
+GTEST_VERSION = release-1.7.0
+GTEST_SITE = $(call github,google,googletest,$(GTEST_VERSION))
 GTEST_INSTALL_STAGING = YES
 GTEST_INSTALL_TARGET = NO
 GTEST_LICENSE = BSD-3c
@@ -22,10 +21,6 @@ GTEST_LICENSE_FILES = LICENSE
 # the gtest sources.
 GTEST_CONF_OPTS = -DBUILD_SHARED_LIBS=OFF
 
-define GTEST_EXTRACT_CMDS
-	$(UNZIP) $(DL_DIR)/$(GTEST_SOURCE) -d $(BUILD_DIR)
-endef
-
 define GTEST_INSTALL_STAGING_CMDS
 	$(INSTALL) -D -m 0755 $(@D)/libgtest.a $(STAGING_DIR)/usr/lib/libgtest.a
 	$(INSTALL) -D -m 0755 $(@D)/libgtest_main.a $(STAGING_DIR)/usr/lib/libgtest_main.a