Use WebKit IDL syntax for declaring optional parameters in dart.idl.

lib/dom/idl/dart/dart.idl

Index: lib/dom/idl/dart/dart.idl
diff --git a/lib/dom/idl/dart/dart.idl b/lib/dom/idl/dart/dart.idl
index 089643559e0f3bc16c480006d0fffbdfca8aa144..5e2fc228c954c03b9f7f7b2f860ae002064c481b 100644
--- a/lib/dom/idl/dart/dart.idl
+++ b/lib/dom/idl/dart/dart.idl
@@ -88,7 +88,7 @@ module html {
 
   [Supplemental]
   interface HTMLOptionsCollection {
-    [Suppressed] void add(in optional HTMLOptionElement element, in optional long before);
+    [Suppressed] void add([Optional] in HTMLOptionElement element, [Optional] in long before);
   };
 
   [Supplemental]
@@ -98,10 +98,10 @@ module html {
 
   [Supplemental]
   interface WebGLContextEvent {
-    [Suppressed] void initEvent(in optional DOMString eventTypeArg,
-                                in optional boolean canBubbleArg,
-                                in optional boolean cancelableArg,
-                                in optional DOMString statusMessageArg);
+    [Suppressed] void initEvent([Optional] in DOMString eventTypeArg,
+                                [Optional] in boolean canBubbleArg,
+                                [Optional] in boolean cancelableArg,
+                                [Optional] in DOMString statusMessageArg);
   };
 };
 
@@ -154,42 +154,42 @@ module canvas {
   [Supplemental]
   interface Float32Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
   [Supplemental]
   interface Float64Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
   [Supplemental]
   interface Int16Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
   [Supplemental]
   interface Int32Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
   [Supplemental]
   interface Int8Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
   [Supplemental]
   interface Uint16Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
   [Supplemental]
   interface Uint32Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
   [Supplemental]
   interface Uint8Array {
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
 
   [Supplemental]
@@ -198,7 +198,7 @@ module canvas {
     [Suppressed] const long BYTES_PER_ELEMENT = 1;
 
     [Suppressed] void set();
-    [DartName=setElements, Custom] void set(in any array, in optional unsigned long offset);
+    [DartName=setElements, Custom] void set(in any array, [Optional] in unsigned long offset);
   };
 };
 
@@ -206,7 +206,7 @@ module storage {
   // TODO(vsm): Define new names for these (see b/4436830).
   [Supplemental]
   interface IDBCursor {
-    [DartName=continueFunction] void continue(in optional IDBKey key);
+    [DartName=continueFunction] void continue([Optional] in IDBKey key);
   };
   [Supplemental]
   interface IDBIndex {