Upgrade to 8.8.10

Created using ./update-from-external.sh 8.8.10

m -j32 droid
adb reboot bootloader
fastboot flashall -w
m -j32 cts
cts-tradefed run cts -m CtsTelephonyTestCases -t android.telephony.cts.PhoneNumberUtilsTest
m -j32 libphonenumber-test vogar dx
vogar --timeout 0 \
    --classpath ${ANDROID_BUILD_TOP}/out/target/common/obj/JAVA_LIBRARIES/libphonenumber-test_intermediates/classes.jar \
        com.google.i18n.phonenumbers

Bug: 65473354
Test: see above
Change-Id: I1fbc05d052f10ac80ec22d5945fde2439c9fedd7
diff --git a/README.version b/README.version
index 7246c69..e29d015 100644
--- a/README.version
+++ b/README.version
@@ -1,3 +1,3 @@
 URL: https://github.com/googlei18n/libphonenumber/
-Version: 8.8.0
+Version: 8.8.10
 BugComponent: 24949