test: stop using chunked encoding for responses (#617)

Author: yury-s

playwright/src/test/java/com/microsoft/playwright/Server.java

@@ -201,23 +201,30 @@ public void handle(HttpExchange exchange) throws IOException {
       return;
     }
     exchange.getResponseHeaders().add("Content-Type", mimeType(file));
-    OutputStream output = exchange.getResponseBody();
+    ByteArrayOutputStream body = new ByteArrayOutputStream();
+    OutputStream output = body;
     if (gzipRoutes.contains(path)) {
       exchange.getResponseHeaders().add("Content-Encoding", "gzip");
     }
     try (FileInputStream input = new FileInputStream(file)) {
-      exchange.sendResponseHeaders(200, 0);
       if (gzipRoutes.contains(path)) {
         output = new GZIPOutputStream(output);
       }
       copy(input, output);
+      output.close();
     } catch (IOException e) {
-      try (Writer writer = new OutputStreamWriter(exchange.getResponseBody())) {
+      body.reset();
+      try (Writer writer = new OutputStreamWriter(output)) {
         writer.write("Exception: " + e);
       }
-      return;
     }
-    output.close();
+    long contentLength = body.size();
+    // -1 means no body, 0 means chunked encoding.
+    exchange.sendResponseHeaders(200, contentLength == 0 ? -1 : contentLength);
+    if (contentLength > 0) {
+      exchange.getResponseBody().write(body.toByteArray());
+    }
+    exchange.getResponseBody().close();
   }
 
   private static String mimeType(File file) {

playwright/src/test/java/com/microsoft/playwright/TestPageNetworkSizes.java

@@ -74,7 +74,6 @@ void shouldSetBodySizeHeadersSizeAndTransferSize() throws ExecutionException, In
   }
 
   @Test
-  @Disabled("responseBodySize == 5")
   void shouldSetBodySizeTo0WhenThereWasNoResponseBody() {
     Response response = page.navigate(server.EMPTY_PAGE);
     Sizes sizes = response.request().sizes();
@@ -83,7 +82,6 @@ void shouldSetBodySizeTo0WhenThereWasNoResponseBody() {
   }
 
   @Test
-  @Disabled("responseBodySize == 0")
   void shouldHaveTheCorrectResponseBodySize() throws IOException {
     Response response = page.navigate(server.PREFIX + "/simplezip.json");
     Sizes sizes = response.request().sizes();