Feature/pre compiled eval scripts (#658)

* Added support of pre-compiled eval expressions

* Added unit tests for eval.Function

* Added RemoteType and RemoteObjectType enums

* Refactored function generation

* Refactored Document and Element loading logic

* Removed redundant fields from cdp.Page

* Exposed eval.Runtime to external callers

* Added new eval.RemoteValue interface

pkg/drivers/cdp/eval/function_compiled.go

@@ -0,0 +1,46 @@
+package eval
+
+import "github.com/mafredri/cdp/protocol/runtime"
+
+type CompiledFunction struct {
+	id  runtime.ScriptID
+	src *Function
+}
+
+func CF(id runtime.ScriptID, src *Function) *CompiledFunction {
+	op := new(CompiledFunction)
+	op.id = id
+	op.src = src
+
+	return op
+}
+
+func (fn *CompiledFunction) returnNothing() *CompiledFunction {
+	fn.src.returnNothing()
+
+	return fn
+}
+
+func (fn *CompiledFunction) returnRef() *CompiledFunction {
+	fn.src.returnRef()
+
+	return fn
+}
+
+func (fn *CompiledFunction) returnValue() *CompiledFunction {
+	fn.src.returnValue()
+
+	return fn
+}
+
+func (fn *CompiledFunction) call(ctx runtime.ExecutionContextID) *runtime.RunScriptArgs {
+	call := runtime.NewRunScriptArgs(fn.id).
+		SetAwaitPromise(fn.src.async).
+		SetReturnByValue(fn.src.returnType == ReturnValue)
+
+	if ctx != EmptyExecutionContextID {
+		call.SetExecutionContextID(ctx)
+	}
+
+	return call
+}