Added update_source.sh script to simplify updating

Bug: 36231644
Test: See following commit
Change-Id: I254bb2aa2e36e0c310d4bda3f3c2d1d873e8f41b
diff --git a/update_source.sh b/update_source.sh
new file mode 100755
index 0000000..b38a072
--- /dev/null
+++ b/update_source.sh
@@ -0,0 +1,67 @@
+#!/bin/bash
+#
+# Copyright 2017 The Android Open Source Project.
+#
+# Retrieves the current Dexmaker to source code into the current directory, excluding portions related
+# to mockito's internal build system and javadoc.
+
+# Force stop on first error.
+set -e
+
+if [ $# -ne 1 ]; then
+    echo "$0 <version>" >&2
+    exit 1;
+fi
+
+if [ -z "$ANDROID_BUILD_TOP" ]; then
+    echo "Missing environment variables. Did you run build/envsetup.sh and lunch?" >&2
+    exit 1
+fi
+
+VERSION=${1}
+
+SOURCE="https://github.com/linkedin/dexmaker"
+INCLUDE="
+    LICENSE
+    dexmaker
+    dexmaker-mockito
+    dexmaker-tests/src
+    "
+
+EXCLUDE="
+    "
+
+working_dir="$(mktemp -d)"
+trap "echo \"Removing temporary directory\"; rm -rf $working_dir" EXIT
+
+echo "Fetching Dexmaker source into $working_dir"
+git clone $SOURCE $working_dir/source
+(cd $working_dir/source; git checkout $VERSION)
+
+for include in ${INCLUDE}; do
+  echo "Updating $include"
+  rm -rf $include
+  mkdir -p $(dirname $include)
+  cp -R $working_dir/source/$include $include
+done;
+
+for exclude in ${EXCLUDE}; do
+  echo "Excluding $exclude"
+  rm -r $exclude
+done;
+
+# Move the dexmaker-tests AndroidManifest.xml into the correct position.
+mv dexmaker-tests/src/main/AndroidManifest.xml dexmaker-tests/AndroidManifest.xml
+
+echo "Updating README.version"
+
+# Update the version.
+perl -pi -e "s|^Version: .*$|Version: ${VERSION}|" "README.version"
+
+# Remove any documentation about local modifications.
+mv README.version README.tmp
+grep -B 100 "Local Modifications" README.tmp > README.version
+echo "        None" >> README.version
+rm README.tmp
+
+echo "Done"