Create ContentShellActivityTestRule and BaseJUnitRunner

content/public/android/BUILD.gn

Index: content/public/android/BUILD.gn
diff --git a/content/public/android/BUILD.gn b/content/public/android/BUILD.gn
index e1b0a4027bbd73d1a8932dd063ebb55229898997..edae83b11709b781d99c41754bf456c04fa2dbbb 100644
--- a/content/public/android/BUILD.gn
+++ b/content/public/android/BUILD.gn
@@ -379,8 +379,10 @@ android_library("content_javatests") {
     "//mojo/public/java:system_java",
     "//net/android:net_java",
     "//net/android:net_java_test_support",
+    "//third_party/android_support_test_runner:rules_java",
     "//third_party/android_support_test_runner:runner_java",
     "//third_party/android_tools:legacy_http_javalib",
+    "//third_party/junit:junit",
     "//ui/android:ui_java",
   ]
 
@@ -392,6 +394,7 @@ android_library("content_javatests") {
     "javatests/src/org/chromium/content/browser/ClipboardTest.java",
     "javatests/src/org/chromium/content/browser/ContentCommandLineTest.java",
     "javatests/src/org/chromium/content/browser/ContentDetectionTestBase.java",
+    "javatests/src/org/chromium/content/browser/ContentDetectionActivityTestRule.java",
     "javatests/src/org/chromium/content/browser/ContentViewCoreSelectionTest.java",
     "javatests/src/org/chromium/content/browser/ContentViewLocationTest.java",
     "javatests/src/org/chromium/content/browser/ContentViewPopupZoomerTest.java",
@@ -411,6 +414,7 @@ android_library("content_javatests") {
     "javatests/src/org/chromium/content/browser/JavaBridgeFieldsTest.java",
     "javatests/src/org/chromium/content/browser/JavaBridgeReturnValuesTest.java",
     "javatests/src/org/chromium/content/browser/JavaBridgeTestBase.java",
+    "javatests/src/org/chromium/content/browser/JavaBridgeActivityTestRule.java",
     "javatests/src/org/chromium/content/browser/LocationProviderTest.java",
     "javatests/src/org/chromium/content/browser/MediaResourceGetterTest.java",
     "javatests/src/org/chromium/content/browser/MediaSessionTest.java",