Remove all DEPS files under //mojo.

mojo/public/cpp/DEPS

Index: mojo/public/cpp/DEPS
diff --git a/mojo/public/cpp/DEPS b/mojo/public/cpp/DEPS
deleted file mode 100644
index 74acd7c7ed30c9918aa5f3645e5976969984076d..0000000000000000000000000000000000000000
--- a/mojo/public/cpp/DEPS
+++ /dev/null
@@ -1,18 +0,0 @@
-include_rules = [
-  # Require explicit dependencies in each directory.
-  "-mojo/public",
-  # But everyone can depend on the C and C++ system headers.
-  "+mojo/public/c/system",
-  "+mojo/public/cpp/system",
-  # Ditto for the C environment headers (but not the C++ environment, since it
-  # has dependencies of its own).
-  "+mojo/public/c/environment",
-]
-
-specific_include_rules = {
-  r".*_(unit|perf)test\.cc": [
-    "+testing",
-    "+mojo/public/cpp/test_support",
-    "+mojo/public/cpp/utility",
-  ],
-}