Introduce KeyframeEffectReadOnly interface

third_party/WebKit/Source/core/animation/KeyframeEffectReadOnly.idl

Index: third_party/WebKit/Source/core/animation/KeyframeEffectReadOnly.idl
diff --git a/third_party/WebKit/Source/core/animation/KeyframeEffectReadOnly.idl b/third_party/WebKit/Source/core/animation/KeyframeEffectReadOnly.idl
new file mode 100644
index 0000000000000000000000000000000000000000..5e733a193dad857046b72c707ff3322327258e85
--- /dev/null
+++ b/third_party/WebKit/Source/core/animation/KeyframeEffectReadOnly.idl
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2013 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+// https://w3c.github.io/web-animations/#the-keyframeeffect-interfaces
+
+[
+    // TODO(dstockwell): the third argument should be "optional (unrestricted double or KeyframeEffectOptions) timing".
+    Constructor(Element? target, (sequence<Dictionary> or Dictionary)? effect, optional unrestricted double timing),
+    Constructor(Element? target, (sequence<Dictionary> or Dictionary)? effect, KeyframeEffectOptions timing),

[alancutter (OOO until 2018), 2016/09/26 07:43:33]

I'm not sure we can expose these constructors just yet. Won't the NOTREACHED()
methods get reached?
Are there tests that create these and use it in animations?

[suzyh_UTC10 (ex-contributor), 2016/09/27 03:44:46]

As discussed offline, I've made the KeyframeEffectReadOnly::create functions
simple wrappers around the mutable class's create functions instead.

+    ConstructorCallWith=ExecutionContext,
+    RaisesException=Constructor,
+    RuntimeEnabled=WebAnimationsAPI,
+] interface KeyframeEffectReadOnly : AnimationEffectReadOnly {
+};