Reduce unnecessary COW on Vector by make writing explicit

This commit makes operator[] on Vector const and adds a write proxy to it.  From
now on writes to Vectors need to happen through the .write proxy. So for
instance:

Vector<int> vec;
vec.push_back(10);
std::cout << vec[0] << std::endl;
vec.write[0] = 20;

Failing to use the .write proxy will cause a compilation error.

In addition COWable datatypes can now embed a CowData pointer to their data.
This means that String, CharString, and VMap no longer use or derive from
Vector.

_ALWAYS_INLINE_ and _FORCE_INLINE_ are now equivalent for debug and non-debug
builds. This is a lot faster for Vector in the editor and while running tests.
The reason why this difference used to exist is because force-inlined methods
used to give a bad debugging experience. After extensive testing with modern
compilers this is no longer the case.

1 files changed, 3 insertions, 3 deletions

diff --git a/modules/visual_script/visual_script.cpp b/modules/visual_script/visual_script.cpp
index 9dea7a9c9e..de9b3d5a91 100644
--- a/modules/visual_script/visual_script.cpp
+++ b/modules/visual_script/visual_script.cpp
@@ -771,7 +771,7 @@ void VisualScript::custom_signal_set_argument_type(const StringName &p_func, int
 	ERR_FAIL_COND(instances.size());
 	ERR_FAIL_COND(!custom_signals.has(p_func));
 	ERR_FAIL_INDEX(p_argidx, custom_signals[p_func].size());
-	custom_signals[p_func][p_argidx].type = p_type;
+	custom_signals[p_func].write[p_argidx].type = p_type;
 }
 Variant::Type VisualScript::custom_signal_get_argument_type(const StringName &p_func, int p_argidx) const {
 
@@ -783,7 +783,7 @@ void VisualScript::custom_signal_set_argument_name(const StringName &p_func, int
 	ERR_FAIL_COND(instances.size());
 	ERR_FAIL_COND(!custom_signals.has(p_func));
 	ERR_FAIL_INDEX(p_argidx, custom_signals[p_func].size());
-	custom_signals[p_func][p_argidx].name = p_name;
+	custom_signals[p_func].write[p_argidx].name = p_name;
 }
 String VisualScript::custom_signal_get_argument_name(const StringName &p_func, int p_argidx) const {
 
@@ -811,7 +811,7 @@ void VisualScript::custom_signal_swap_argument(const StringName &p_func, int p_a
 	ERR_FAIL_INDEX(p_argidx, custom_signals[p_func].size());
 	ERR_FAIL_INDEX(p_with_argidx, custom_signals[p_func].size());
 
-	SWAP(custom_signals[p_func][p_argidx], custom_signals[p_func][p_with_argidx]);
+	SWAP(custom_signals[p_func].write[p_argidx], custom_signals[p_func].write[p_with_argidx]);
 }
 void VisualScript::remove_custom_signal(const StringName &p_name) {