[webcrypto] Add support for import/export of "raw" formatted EC keys.

components/webcrypto/algorithms/ec.h

Index: components/webcrypto/algorithms/ec.h
diff --git a/components/webcrypto/algorithms/ec.h b/components/webcrypto/algorithms/ec.h
index 1484ad8114dbe1d212c607f171064ec1390b8c4a..048bc50e5a5526b30e949f12ca8fdf6161404c0d 100644
--- a/components/webcrypto/algorithms/ec.h
+++ b/components/webcrypto/algorithms/ec.h
@@ -51,6 +51,12 @@ class EcAlgorithm : public AlgorithmImplementation {
                                 blink::WebCryptoKey* key) const override;
 
  private:
+  Status ImportKeyRaw(const CryptoData& key_data,
+                      const blink::WebCryptoAlgorithm& algorithm,
+                      bool extractable,
+                      blink::WebCryptoKeyUsageMask usages,
+                      blink::WebCryptoKey* key) const;
+
   Status ImportKeyPkcs8(const CryptoData& key_data,
                         const blink::WebCryptoAlgorithm& algorithm,
                         bool extractable,
@@ -69,6 +75,9 @@ class EcAlgorithm : public AlgorithmImplementation {
                       blink::WebCryptoKeyUsageMask usages,
                       blink::WebCryptoKey* key) const;
 
+  Status ExportKeyRaw(const blink::WebCryptoKey& key,
+                      std::vector<uint8_t>* buffer) const;
+
   Status ExportKeyPkcs8(const blink::WebCryptoKey& key,
                         std::vector<uint8_t>* buffer) const;