Rename google-java-format's placeholder .jar to accommodate depot_tools
change

See: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/7130803

Bug: 456461246
Change-Id: Iffa95e2d90a6b12d84d1392b2b068efe4ec8e374

third_party/google-java-format/README.md

diff --git a/third_party/google-java-format/README.md b/third_party/google-java-format/README.md
new file mode 100644
index 0000000..fc6ca7f
--- /dev/null
+++ b/third_party/google-java-format/README.md
@@ -0,0 +1,7 @@
+This directory is required for `git cl format` to format Java code.
+
+The command looks for a `google-java-format.jar` file, and then runs the
+`google-java-format` script.
+
+The `google-java-format.jar` in this directory is just a placeholder, since the
+real on lives in `//third_party/google/...`

third_party/google-java-format/google-java-format.jar

diff --git a/third_party/google-java-format/placeholder.jar b/third_party/google-java-format/google-java-format.jar
similarity index 100%
rename from third_party/google-java-format/placeholder.jar
rename to third_party/google-java-format/google-java-format.jar