Coalesce small buffers in net::BidirectionalStream

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

Index: components/cronet/android/api/src/org/chromium/net/BidirectionalStream.java
diff --git a/components/cronet/android/api/src/org/chromium/net/BidirectionalStream.java b/components/cronet/android/api/src/org/chromium/net/BidirectionalStream.java
index 5b6d04bfc427ba4052019ed18cb7c70cbb54004f..e4fdfe2a1910ff453a20e6509e3015189693b79c 100644
--- a/components/cronet/android/api/src/org/chromium/net/BidirectionalStream.java
+++ b/components/cronet/android/api/src/org/chromium/net/BidirectionalStream.java
@@ -47,6 +47,8 @@ public abstract class BidirectionalStream {
         // Priority of the stream. Default is medium.
         @StreamPriority private int mPriority = STREAM_PRIORITY_MEDIUM;
 
+        private boolean mDisableAutoFlush;
+
         /**
          * Creates a builder for {@link BidirectionalStream} objects. All callbacks for
          * generated {@code BidirectionalStream} objects will be invoked on
@@ -160,6 +162,17 @@ public abstract class BidirectionalStream {
         }
 
         /**
+         * By default, data is flushed after every {@link #write write()}. This
+         * is to disable auto flush.
+         * @param disableAutoFlush if true, auto flush will be disabled.
+         * @return the builder to facilitate chaining.
+         */
+        public Builder disableAutoFlush(boolean disableAutoFlush) {
+            mDisableAutoFlush = disableAutoFlush;
+            return this;
+        }
+
+        /**
          * Creates a {@link BidirectionalStream} using configuration from this
          * {@link Builder}. The returned {@code BidirectionalStream} can then be started
          * by calling {@link BidirectionalStream#start}.
@@ -168,8 +181,8 @@ public abstract class BidirectionalStream {
          *         this {@link Builder}
          */
         public BidirectionalStream build() {
-            return mCronetEngine.createBidirectionalStream(
-                    mUrl, mCallback, mExecutor, mHttpMethod, mRequestHeaders, mPriority);
+            return mCronetEngine.createBidirectionalStream(mUrl, mCallback, mExecutor, mHttpMethod,
+                    mRequestHeaders, mPriority, mDisableAutoFlush);
         }
     }
 
@@ -178,17 +191,19 @@ public abstract class BidirectionalStream {
      */
     public abstract static class Callback {
         /**
-         * Invoked when request headers are sent. Indicates that stream has initiated the request.
-         * Consumer may call {@link BidirectionalStream#write write()} to start writing data.
+         * Invoked when the stream is ready for reading and writing.
+         * Consumer may call {@link BidirectionalStream#read read()} to start
+         * reading. Consumer may call {@link BidirectionalStream#write write()}
+         * to start writing data.
          *
-         * @param stream the stream on which request headers were sent
+         * @param stream the stream that is ready
          */
-        public abstract void onRequestHeadersSent(BidirectionalStream stream);
+        public abstract void onStreamReady(BidirectionalStream stream);
 
         /**
          * Invoked when initial response headers are received. Headers are available from
          * {@code info.}{@link UrlResponseInfo#getAllHeaders getAllHeaders()}.
-         * Consumer must call {@link BidirectionalStream#read read()} to start reading.
+         * Consumer may call {@link BidirectionalStream#read read()} to start reading.
          * Consumer may call {@link BidirectionalStream#write write()} to start writing or close the
          * stream.
          *
@@ -315,6 +330,7 @@ public abstract class BidirectionalStream {
     /**
      * Reads data from the stream into the provided buffer.
      * Must only be called at most once in response to each invocation of the
+     * {@link Callback#onStreamReady onStreamReady()},
      * {@link Callback#onResponseHeadersReceived onResponseHeadersReceived()} and {@link
      * Callback#onReadCompleted onReadCompleted()} methods of the {@link
      * Callback}. Each call will result in an invocation of one of the
@@ -340,7 +356,7 @@ public abstract class BidirectionalStream {
     /**
      * Attempts to write data from the provided buffer into the stream.
      * Must only be called at most once in response to each invocation of the
-     * {@link Callback#onRequestHeadersSent onRequestHeadersSent()} or {@link
+     * {@link Callback#onStreamReady onStreamReady()} or {@link
      * Callback#onWriteCompleted onWriteCompleted()} methods of the {@link Callback}.
      * Each call will result in an asynchronous call to one of the {@link Callback Callback}'s
      * {@link Callback#onWriteCompleted onWriteCompleted()} method if data
@@ -365,6 +381,12 @@ public abstract class BidirectionalStream {
     public abstract void write(ByteBuffer buffer, boolean endOfStream);
 
     /**
+     * Flushes pending writes. This method should only be invoked when auto
+     * flush is disabled through {@link Builder#disableAutoFlush}.
+     */
+    public abstract void flush();
+
+    /**
      * Pings remote end-point. {@code callback} methods will be invoked on {@code executor}.
      *
      * @param callback the callback that will be invoked when ping succeeds or fails