Revert of Fix android_junit_tests and add a GN target for them.

webrtc/BUILD.gn

Index: webrtc/BUILD.gn
diff --git a/webrtc/BUILD.gn b/webrtc/BUILD.gn
index e2d6710965a3c4ac3f2a8e9b47345f282267c460..2d722c91259ef29abcdcd8584619ce0a748c17a5 100644
--- a/webrtc/BUILD.gn
+++ b/webrtc/BUILD.gn
@@ -12,10 +12,6 @@
 import("//build/config/sanitizers/sanitizers.gni")
 import("build/webrtc.gni")
 import("//third_party/protobuf/proto_library.gni")
-if (is_android) {
-  import("//build/config/android/config.gni")
-  import("//build/config/android/rules.gni")
-}
 
 # Contains the defines and includes in common.gypi that are duplicated both as
 # target_defaults and direct_dependent_settings.
@@ -836,14 +832,3 @@
     }
   }
 }
-
-if (is_android) {
-  junit_binary("android_junit_tests") {
-    java_files = [ "androidjunit/src/org/webrtc/CameraEnumerationTest.java" ]
-
-    deps = [
-      "//webrtc/api:libjingle_peerconnection_java",
-      "//webrtc/api:libjingle_peerconnection_jni",
-    ]
-  }
-}