[refactor] Use a lookup table rather than binary search for algorithm normalization.

public/platform/WebCrypto.h

Index: public/platform/WebCrypto.h
diff --git a/public/platform/WebCrypto.h b/public/platform/WebCrypto.h
index 8ee33e67d552030dda5b1150a13459703dfa9545..a52ae8ffed310ee8a3361856b09bc2113f2a28b3 100644
--- a/public/platform/WebCrypto.h
+++ b/public/platform/WebCrypto.h
@@ -193,11 +193,12 @@ public:
     // them, as they come directly from the user. Few checks have been done on
     // algorithm parameters prior to passing to the embedder.
     //
-    // Only the following checks can be assumed as having alread passed:
+    // Only the following checks can be assumed as having already passed:
     //
     //  * The key is extractable when calling into exportKey/wrapKey.
     //  * The key usages permit the operation being requested.
     //  * The key's algorithm matches that of the requested operation.
+    //  * When creating a key, the key usages are appropriate for the algorithm.
     //
     virtual void encrypt(const WebCryptoAlgorithm&, const WebCryptoKey&, const unsigned char* data, unsigned dataSize, WebCryptoResult result) { result.completeWithError(WebCryptoErrorTypeNotSupported, ""); }
     virtual void decrypt(const WebCryptoAlgorithm&, const WebCryptoKey&, const unsigned char* data, unsigned dataSize, WebCryptoResult result) { result.completeWithError(WebCryptoErrorTypeNotSupported, ""); }