Move the unit tests files side-by-side with the corresponding .cc files.

components/update_client/DEPS

Index: components/update_client/DEPS
diff --git a/components/update_client/DEPS b/components/update_client/DEPS
index 79e034989c4037cf3319450e032ffa3ad242fc19..7fa716527b183e620b3ca0ed48426c3224c2bd9e 100644
--- a/components/update_client/DEPS
+++ b/components/update_client/DEPS
@@ -8,5 +8,13 @@ include_rules = [
   "+ui/base/win",
   "+third_party/libxml",
   "+third_party/zlib",
-  "+testing",
 ]
+
+# Tests can use things in content.
+# TODO(sorin): refactor to eliminate the dependency on content by using
+# message loops directly.
+specific_include_rules = {
+  ".*unittest\.cc": [
+    "+content",
+  ]
+}