wasm-executor: Support growing the memory (paritytech#12520)

* As always, start with something :P

* Add support for max_heap_pages

* Add support for wasmtime

* Make it compile

* Fix compilation

* Copy wrongly merged code

* Fix compilation

* Some fixes

* Fix

* Get stuff working

* More work

* More fixes

* ...

* More

* FIXEs

* Switch wasmi to use `RuntimeBlob` like wasmtime

* Removed unused stuff

* Cleanup

* More cleanups

* Introduce `CallContext`

* Fixes

* More fixes

* Add builder for creating the `WasmExecutor`

* Adds some docs

* FMT

* First round of feedback.

* Review feedback round 2

* More fixes

* Fix try-runtime

* Update client/executor/wasmtime/src/instance_wrapper.rs

Co-authored-by: Koute <koute@users.noreply.github.com>

* Update client/executor/common/src/wasm_runtime.rs

Co-authored-by: Koute <koute@users.noreply.github.com>

* Update client/executor/common/src/runtime_blob/runtime_blob.rs

Co-authored-by: Koute <koute@users.noreply.github.com>

* Update client/executor/common/src/wasm_runtime.rs

Co-authored-by: Koute <koute@users.noreply.github.com>

* Update client/allocator/src/freeing_bump.rs

Co-authored-by: Koute <koute@users.noreply.github.com>

* Update client/allocator/src/freeing_bump.rs

Co-authored-by: Koute <koute@users.noreply.github.com>

* Feedback round 3

* FMT

* Review comments

---------

Co-authored-by: Koute <koute@users.noreply.github.com>

client/executor/wasmi/src/lib.rs

@@ -28,14 +28,13 @@ use wasmi::{
 	TableRef,
 };
 
-use codec::{Decode, Encode};
-use sc_allocator::AllocationStats;
+use sc_allocator::{AllocationStats, FreeingBumpHeapAllocator};
 use sc_executor_common::{
 	error::{Error, MessageWithBacktrace, WasmError},
 	runtime_blob::{DataSegmentsSnapshot, RuntimeBlob},
 	sandbox::{self, SandboxInstance},
 	util::MemoryTransfer,
-	wasm_runtime::{InvokeMethod, WasmInstance, WasmModule},
+	wasm_runtime::{HeapAllocStrategy, InvokeMethod, WasmInstance, WasmModule},
 };
 use sp_runtime_interface::unpack_ptr_and_len;
 use sp_sandbox::env as sandbox_env;