block cleanup (#9117)

* blockchain insert expects owned block instead of block reference

* reduce a number of times a block is deserialized

* removed cached uncle_bytes from block

* removed is_finalized from OpenBlock

* removed unused parity_machine::WithMetadata trait

* removed commented out code

* remove unused metadata from block

* remove unused metadata from block

* BlockDetails extras may have at most 5 elements

ethcore/src/header.rs

@@ -43,8 +43,6 @@ pub struct ExtendedHeader {
 	pub is_finalized: bool,
 	/// The parent block difficulty.
 	pub parent_total_difficulty: U256,
-	/// The block metadata information.
-	pub metadata: Option<Vec<u8>>,
 }
 
 /// A block header.
@@ -418,10 +416,6 @@ impl ::parity_machine::FinalizableHeader for ExtendedHeader {
 	fn is_finalized(&self) -> bool { self.is_finalized }
 }
 
-impl ::parity_machine::WithMetadataHeader for ExtendedHeader {
-	fn metadata(&self) -> Option<&[u8]> { self.metadata.as_ref().map(|v| v.as_ref()) }
-}
-
 #[cfg(test)]
 mod tests {
 	use rustc_hex::FromHex;