wasm-executor: Support growing the memory (#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>

substrate/primitives/core/src/traits.rs

@@ -24,13 +24,27 @@ use std::{
 
 pub use sp_externalities::{Externalities, ExternalitiesExt};
 
+/// The context in which a call is done.
+///
+/// Depending on the context the executor may chooses different kind of heap sizes for the runtime
+/// instance.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Ord, PartialOrd)]
+pub enum CallContext {
+	/// The call is happening in some offchain context.
+	Offchain,
+	/// The call is happening in some on-chain context like building or importing a block.
+	Onchain,
+}
+
 /// Code execution engine.
 pub trait CodeExecutor: Sized + Send + Sync + ReadRuntimeVersion + Clone + 'static {
 	/// Externalities error type.
 	type Error: Display + Debug + Send + Sync + 'static;
 
-	/// Call a given method in the runtime. Returns a tuple of the result (either the output data
-	/// or an execution error) together with a `bool`, which is true if native execution was used.
+	/// Call a given method in the runtime.
+	///
+	/// Returns a tuple of the result (either the output data or an execution error) together with a
+	/// `bool`, which is true if native execution was used.
 	fn call(
 		&self,
 		ext: &mut dyn Externalities,
@@ -38,6 +52,7 @@ pub trait CodeExecutor: Sized + Send + Sync + ReadRuntimeVersion + Clone + 'stat
 		method: &str,
 		data: &[u8],
 		use_native: bool,
+		context: CallContext,
 	) -> (Result<Vec<u8>, Self::Error>, bool);
 }