Refactor task arguments to be a single one (vercel/turborepo#8736)

### Description

As preparation to pass a struct only, we change the task arguments to be
a single one

### Testing Instructions

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  Give a quick description of steps to test your changes.
-->

crates/turbo-tasks-macros/src/derive/task_input_macro.rs

@@ -123,7 +123,7 @@ pub fn derive_task_input(input: TokenStream) -> TokenStream {
                                 _ => return Err(anyhow::anyhow!("invalid discriminant for {}", stringify!(#ident))),
                             })
                         },
-                        _ => Err(anyhow::anyhow!("invalid task input type, expected list")),
+                        _ => Err(anyhow::anyhow!("invalid task input type, expected list (enum)")),
                     }
                 },
                 quote! {
@@ -155,7 +155,7 @@ pub fn derive_task_input(input: TokenStream) -> TokenStream {
                             #try_from_expansion
                             Ok(#ident #destructuring)
                         },
-                        _ => Err(anyhow::anyhow!("invalid task input type, expected list")),
+                        _ => Err(anyhow::anyhow!("invalid task input type, expected list (struct)")),
                     }
                 },
                 quote! {

crates/turbo-tasks-macros/src/func.rs

@@ -326,7 +326,7 @@ impl TurboFn {
                             *#trait_type_id_ident,
                             std::borrow::Cow::Borrowed(stringify!(#ident)),
                             #converted_this,
-                            vec![#converted_inputs],
+                            turbo_tasks::TaskInput::into_concrete((#converted_inputs)),
                         )
                     )
                 }
@@ -352,7 +352,7 @@ impl TurboFn {
                         turbo_tasks::dynamic_this_call(
                             *#native_function_id_ident,
                             #converted_this,
-                            vec![#converted_inputs],
+                            turbo_tasks::TaskInput::into_concrete((#converted_inputs)),
                         )
                     )
                 }
@@ -363,7 +363,7 @@ impl TurboFn {
                     <#output as turbo_tasks::task::TaskOutput>::try_from_raw_vc(
                         turbo_tasks::dynamic_call(
                             *#native_function_id_ident,
-                            vec![#converted_inputs],
+                            turbo_tasks::TaskInput::into_concrete((#converted_inputs)),
                         )
                     )
                 }

crates/turbo-tasks-memory/src/lib.rs

@@ -14,11 +14,9 @@ mod edges_set;
 mod gc;
 mod map_guard;
 mod memory_backend;
-mod memory_backend_with_pg;
 mod output;
 mod task;
 mod task_statistics;
 
 pub use memory_backend::MemoryBackend;
-pub use memory_backend_with_pg::MemoryBackendWithPersistedGraph;
 pub use task_statistics::{TaskStatistics, TaskStatisticsApi};

crates/turbo-tasks-memory/src/memory_backend.rs

@@ -548,20 +548,20 @@ impl Backend for MemoryBackend {
                 PersistentTaskType::ResolveNative {
                     fn_type: function_id,
                     this: _,
-                    args: _,
+                    arg: _,
                 }
                 | PersistentTaskType::Native {
                     fn_type: function_id,
                     this: _,
-                    args: _,
+                    arg: _,
                 } => {
                     stats.increment_cache_hit(*function_id);
                 }
                 PersistentTaskType::ResolveTrait {
                     trait_type,
                     method_name: name,
                     this,
-                    args: _,
+                    arg: _,
                 } => {
                     // HACK: Resolve the this argument (`self`) in order to attribute the cache hit
                     // to the concrete trait implementation, rather than the dynamic trait method.
@@ -595,7 +595,7 @@ impl Backend for MemoryBackend {
                 PersistentTaskType::Native {
                     fn_type: function_id,
                     this: _,
-                    args: _,
+                    arg: _,
                 } => {
                     stats.increment_cache_miss(*function_id);
                 }