Unit tests for importing prefs from the Java side implemented

components/variations/BUILD.gn

Index: components/variations/BUILD.gn
diff --git a/components/variations/BUILD.gn b/components/variations/BUILD.gn
index a65148ae55af9d617d34bfc1a505084691f162b5..9ef0d9cc7103b66861b3625413df80f4f5725ed6 100644
--- a/components/variations/BUILD.gn
+++ b/components/variations/BUILD.gn
@@ -62,7 +62,6 @@ source_set("variations") {
   }
 
   deps = [
-    "proto",
     "//base",
     "//base:prefs",
     "//components/compression",
@@ -70,6 +69,7 @@ source_set("variations") {
     "//crypto",
     "//third_party/mt19937ar",
     "//third_party/protobuf:protobuf_lite",
+    "proto",
   ]
 
   if (is_android) {
@@ -88,6 +88,15 @@ if (is_android) {
   }
 }
 
+if (is_android) {
+  generate_jni("variations_jni_test_headers") {
+    sources = [
+      "android/java/src/org/chromium/components/variations/firstrun/VariationsSeedBridgeTest.java",
+    ]
+    jni_package = "variations"
+  }
+}
+
 source_set("unit_tests") {
   testonly = true
   sources = [
@@ -109,13 +118,21 @@ source_set("unit_tests") {
     sources += [ "variations_request_scheduler_mobile_unittest.cc" ]
   }
 
+  if (is_android) {
+    sources += [
+      "android/variations_seed_bridge_test.cc",
+      "android/variations_seed_bridge_test.h",
+    ]
+  }
+
   deps = [
     ":variations",
-    "net",
-    "proto",
+    ":variations_jni_test_headers",
     "//base:prefs_test_support",
     "//base/test:test_support",
     "//components/compression",
     "//testing/gtest",
+    "net",
+    "proto",
   ]
 }