[Cronet] Add ExperimentalCronetEngine.Builder.setThreadPriority() API

components/cronet/android/api/src/org/chromium/net/ExperimentalCronetEngine.java

Index: components/cronet/android/api/src/org/chromium/net/ExperimentalCronetEngine.java
diff --git a/components/cronet/android/api/src/org/chromium/net/ExperimentalCronetEngine.java b/components/cronet/android/api/src/org/chromium/net/ExperimentalCronetEngine.java
index 0168249cf1cd4319cb5ac660aad5e91395cf91b0..9ab5f648e77d91a56f64f62f9a0a044273373563 100644
--- a/components/cronet/android/api/src/org/chromium/net/ExperimentalCronetEngine.java
+++ b/components/cronet/android/api/src/org/chromium/net/ExperimentalCronetEngine.java
@@ -149,6 +149,23 @@ public abstract class ExperimentalCronetEngine extends CronetEngine {
             return this;
         }
 
+        /**
+         * Sets the thread priority of Cronet's internal thread.
+         *
+         * @param priority the thread priority of Cronet's internal thread.
+         *        A Linux priority level, from -20 for highest scheduling
+         *        priority to 19 for lowest scheduling priority. For more
+         *        information on values, see
+         *        {@link android.os.Process#setThreadPriority(int, int)} and
+         *        {@link android.os.Process#THREAD_PRIORITY_DEFAULT
+         *        THREAD_PRIORITY_*} values.
+         * @return the builder to facilitate chaining.
+         */
+        public Builder setThreadPriority(int priority) {
+            mBuilderDelegate.setThreadPriority(priority);
+            return this;
+        }
+
         /**
          * Returns delegate, only for testing.
          * @hide