Add LayoutTests for WebCrypto's ECDH algorithm.

LayoutTests/crypto/ecdh-import-jwk.html

Index: LayoutTests/crypto/ecdh-import-jwk.html
diff --git a/LayoutTests/crypto/ecdsa-import-jwk.html b/LayoutTests/crypto/ecdh-import-jwk.html
similarity index 77%
copy from LayoutTests/crypto/ecdsa-import-jwk.html
copy to LayoutTests/crypto/ecdh-import-jwk.html
index 76b53d185958d83c507bfa43e0ec79978cfb78a5..70af32665c9c47bac6a4199a1fb081d756c167a9 100644
--- a/LayoutTests/crypto/ecdsa-import-jwk.html
+++ b/LayoutTests/crypto/ecdh-import-jwk.html
@@ -9,7 +9,7 @@
 <div id="console"></div>
 
 <script>
-description("Test importing an EC public and private key for ECDSA.");
+description("Test importing an EC public and private key for ECDH.");
 
 jsTestIsAsync = true;
 
@@ -31,21 +31,21 @@ var privateKeyJSON = {
 };
 
 debug("Importing a public key...");
-crypto.subtle.importKey("jwk", publicKeyJSON, {name: "ECDSA", namedCurve: "P-256"}, extractable, ["verify"]).then(function(result) {
+crypto.subtle.importKey("jwk", publicKeyJSON, {name: "ECDH", namedCurve: "P-256"}, extractable, []).then(function(result) {
     publicKey = result;
     shouldBe("publicKey.toString()", "'[object CryptoKey]'");
     shouldBe("publicKey.type", "'public'");
-    shouldBe("publicKey.usages", "['verify']");
-    shouldBe("publicKey.algorithm.name", "'ECDSA'");
+    shouldBe("publicKey.usages", "[]");
+    shouldBe("publicKey.algorithm.name", "'ECDH'");
     shouldBe("publicKey.algorithm.namedCurve", "'P-256'");
     debug("\nImporting a private key...");
-    return crypto.subtle.importKey("jwk", privateKeyJSON, {name: "ECDSA", namedCurve: "P-384"}, extractable, ["sign"]);
+    return crypto.subtle.importKey("jwk", privateKeyJSON, {name: "ECDH", namedCurve: "P-384"}, extractable, ["deriveBits"]);
 }).then(function(result) {
     privateKey = result;
     shouldBe("privateKey.toString()", "'[object CryptoKey]'");
     shouldBe("privateKey.type", "'private'");
-    shouldBe("privateKey.usages", "['sign']");
-    shouldBe("privateKey.algorithm.name", "'ECDSA'");
+    shouldBe("privateKey.usages", "['deriveBits']");
+    shouldBe("privateKey.algorithm.name", "'ECDH'");
     shouldBe("privateKey.algorithm.namedCurve", "'P-384'");
 }).then(finishJSTest, failAndFinishJSTest); 
 </script>