Integrate WASM IndexedDb jl777#928 (jl777#952)

* Refactor `ws_transport`, `spawn_ws_transport` error types
* Remove the `WebSocketError::UnderlyingError` error

* Integrate the browser 'IndexedDb' database
* Add wasm_indexed_db.rs
* Implement the `IndexedDb` initialization

* Fix the 'common' crate warnings
* Remove 'allow(dead_code)' for wasm32 arch
* Remove 'allow(unused_import)' for wasm32 arch
* Add the 'cfg_wasm32', 'cfg_native' macros
* Separated 'WasmUnwrapExt' into 'WasmUnwrapExt' and 'WasmUnwrapErrExt'

* Refactor `IndexedDb`
* Add `IndexedDbBuilder`
* Add 'DbTransaction'

* Add add/get items methods to 'IndexedDb'
* Add 'IndexedDb::add_item', 'IndexedDb::get_items'
* Refactor wasm_ws tests

* Add 'IndexedDb::replace_item'

* Add the aborted flag to the open table/transaction

* Add 'DbTable::get_item_ids'

* Add 'TxHistoryDb' with the implementation depending on the arch
* Add common::panic_w
* Add 'DbTable::clear' method

* Add 'TxHistoryDb' with the implementation depending on the arch
* Add 'DbTable::delete_item' method, use it on 'TxHistory::clear'
* Separate 'wasm_indexed_db::tests::test_add_get_item' to itself, 'test_replace_item', 'test_delete_item', 'test_clear'

* Make the reading/changing tx history non-blocking

* Fix rustfmt warnings

* Replace tokio::fs with async_std::fs
* Use ticker and wallet_address to identify the history items

mm2src/coins/Cargo.toml

@@ -9,13 +9,15 @@ path = "lp_coins.rs"
 doctest = false
 
 [dependencies]
+async-std = { version = "1.5", features = ["unstable"] }
 async-trait = "0.1"
 base64 = "0.10.0"
 bigdecimal = { version = "0.1.0", features = ["serde"] }
 bitcoin-cash-slp = "0.3.1"
 bitcrypto = { git = "https://github.com/artemii235/parity-bitcoin.git" }
 byteorder = "1.3"
 bytes = "0.4"
+cfg-if = "1.0"
 chain = { git = "https://github.com/artemii235/parity-bitcoin.git" }
 common = { path = "../common" }
 derive_more = "0.99"

mm2src/coins/lp_coins.rs

@@ -96,6 +96,8 @@ use qrc20::{qrc20_coin_from_conf_and_request, Qrc20Coin, Qrc20FeeDetails};
 pub mod test_coin;
 pub use test_coin::TestCoin;
 
+pub mod tx_history_db;
+
 #[cfg(not(target_arch = "wasm32"))] pub mod z_coin;
 
 pub type BalanceResult<T> = Result<T, MmError<BalanceError>>;