Fixed more HttpRequest documentation.

tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate

Index: tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate b/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
index 7919df9cb26bfb3076192fcfdb7a791c0bf60a3d..646d6c3e2a8fdd1234eb81111227b40afa7cf3b5 100644
--- a/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
+++ b/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
@@ -54,8 +54,9 @@ $(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
   /**
    * Makes a server POST request with the specified data encoded as form data.
    *
-   * This is similar to sending a FormData object with broader browser
-   * support but limited to string values.
+   * This is roughly the POST equivalent of getString. This method is similar 
+   * to sending a FormData object with broader browser support but limited to 
+   * String values.
    *
    * See also:
    *
@@ -88,11 +89,15 @@ $(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
   /**
    * Creates a URL request for the specified [url].
    *
-   * By default this will do an HTTP GET request, this can be overridden with
-   * [method].
+   * By default `request` will perform an HTTP GET request, but a different
+   * method (`POST`, `PUT`, `DELETE`, etc) can be used by specifying the 
+   * [method] parameter.
    *
    * The Future is completed when the response is available.
    *
+   * If specified, `sendData` will send data in the form of a [ByteBuffer],
+   * [Blob], [Document], [String], or [FormData] along with the HttpRequest.
+   *
    * The [withCredentials] parameter specified that credentials such as a cookie
    * (already) set in the header or
    * [authorization headers](http://tools.ietf.org/html/rfc1945#section-10.2)