Fix warnings about set but unused variables [-Wunused-but-set-variable]

Fixes the following GCC 5 warnings:
```
drivers/gles2/rasterizer_canvas_gles2.cpp:814:8: warning: variable 'rt_size' set but not used [-Wunused-but-set-variable]
drivers/gles2/rasterizer_scene_gles2.cpp:2270:11: warning: variable 'vp_height' set but not used [-Wunused-but-set-variable]
drivers/gles2/rasterizer_scene_gles2.cpp:2673:22: warning: variable 'e' set but not used [-Wunused-but-set-variable]
drivers/gles2/rasterizer_scene_gles2.cpp:715:7: warning: variable 'no_cull' set but not used [-Wunused-but-set-variable]
drivers/gles2/shader_gles2.cpp:693:14: warning: variable 'cc' set but not used [-Wunused-but-set-variable]
drivers/gles3/rasterizer_canvas_gles3.cpp:1226:8: warning: variable 'rt_size' set but not used [-Wunused-but-set-variable]
drivers/gles3/rasterizer_scene_gles3.cpp:3039:10: warning: variable 'contrib' set but not used [-Wunused-but-set-variable]
drivers/gles3/rasterizer_scene_gles3.cpp:4504:32: warning: variable 'vp_height' set but not used [-Wunused-but-set-variable]
editor/editor_inspector.cpp:272:9: warning: variable 'guide_color' set but not used [-Wunused-but-set-variable]
editor/editor_themes.cpp:1067:14: warning: variable 'alpha3' set but not used [-Wunused-but-set-variable]
editor/editor_themes.cpp:263:8: warning: variable 'script_bg_color' set but not used [-Wunused-but-set-variable]
editor/plugins/collision_shape_2d_editor_plugin.cpp:326:11: warning: variable 'cpoint' set but not used [-Wunused-but-set-variable]
editor/plugins/mesh_editor_plugin.cpp:72:9: warning: variable 'size' set but not used [-Wunused-but-set-variable]
editor/plugins/shader_editor_plugin.cpp:471:12: warning: variable 'mpos' set but not used [-Wunused-but-set-variable]
editor/plugins/shader_editor_plugin.cpp:89:8: warning: variable 'basetype_color' set but not used [-Wunused-but-set-variable]
editor/plugins/shader_editor_plugin.cpp:90:8: warning: variable 'type_color' set but not used [-Wunused-but-set-variable]
editor/plugins/shader_editor_plugin.cpp:92:8: warning: variable 'string_color' set but not used [-Wunused-but-set-variable]
modules/visual_script/visual_script_editor.cpp:2521:7: warning: variable 'seq_connect' set but not used [-Wunused-but-set-variable]
platform/android/export/export.cpp:580:12: warning: variable 'styles_count' set but not used [-Wunused-but-set-variable]
platform/android/export/export.cpp:584:12: warning: variable 'styles_offset' set but not used [-Wunused-but-set-variable]
platform/osx/export/export.cpp:464:9: warning: variable 'zerr' set but not used [-Wunused-but-set-variable]
scene/2d/tile_map.cpp:260:10: warning: variable 'tcenter' set but not used [-Wunused-but-set-variable]
scene/3d/light.cpp:166:7: warning: variable 'editor_ok' set but not used [-Wunused-but-set-variable]
scene/3d/navigation.cpp:566:11: warning: variable 'closest_navmesh' set but not used [-Wunused-but-set-variable]
scene/gui/rich_text_label.cpp:869:8: warning: variable 'size' set but not used [-Wunused-but-set-variable]
scene/main/viewport.cpp:705:14: warning: variable 'xform' set but not used [-Wunused-but-set-variable]
scene/main/viewport.cpp:706:8: warning: variable 'ss' set but not used [-Wunused-but-set-variable]
scene/main/viewport.cpp:726:14: warning: variable 'xform' set but not used [-Wunused-but-set-variable]
scene/main/viewport.cpp:727:8: warning: variable 'ss' set but not used [-Wunused-but-set-variable]
scene/resources/material.cpp:430:7: warning: variable 'using_world' set but not used [-Wunused-but-set-variable]
servers/visual/shader_language.cpp:2026:7: warning: variable 'all_const' set but not used [-Wunused-but-set-variable]
servers/visual/visual_server_scene.cpp:1383:28: warning: variable 'z_max_cam' set but not used [-Wunused-but-set-variable]
```

Also fixes two [-Wunused-value] warnings:
```
scene/gui/text_edit.cpp:4405:20: warning: statement has no effect [-Wunused-value]
servers/visual/visual_server_scene.cpp:905:48: warning: value computed is not used [-Wunused-value]
```

Some of those are bugs and need further work, they are identified with
`// FIXME` comments.

2 files changed, 0 insertions, 13 deletions

diff --git a/modules/visual_script/visual_script_editor.cpp b/modules/visual_script/visual_script_editor.cpp
index f4e7d9831a..79f71535ad 100644
--- a/modules/visual_script/visual_script_editor.cpp
+++ b/modules/visual_script/visual_script_editor.cpp
@@ -2518,8 +2518,6 @@ void VisualScriptEditor::_port_action_menu(int p_option) {
 	}
 	ofs /= EDSCALE;
 
-	bool seq_connect = false;
-
 	Set<int> vn;
 
 	switch (p_option) {
@@ -2552,7 +2550,6 @@ void VisualScriptEditor::_port_action_menu(int p_option) {
 			}
 		} break;
 		case CREATE_ACTION: {
-			seq_connect = true;
 			VisualScriptNode::TypeGuess tg = _guess_output_type(port_action_node, port_action_output, vn);
 			PropertyInfo property_info = script->get_node(edited_func, port_action_node)->get_output_value_port_info(port_action_output);
 			if (tg.type == Variant::OBJECT) {
@@ -2656,7 +2653,6 @@ void VisualScriptEditor::_selected_connect_node(const String &p_text, const Stri
 
 	Ref<VisualScriptNode> vnode;
 
-	seq_connect = false;
 	if (p_category == String("method")) {
 
 		Ref<VisualScriptFunctionCall> n;
@@ -2682,38 +2678,32 @@ void VisualScriptEditor::_selected_connect_node(const String &p_text, const Stri
 			Ref<VisualScriptCondition> n;
 			n.instance();
 			vnode = n;
-			seq_connect = true;
 		}
 		if (p_text == "VisualScriptSwitch") {
 
 			Ref<VisualScriptSwitch> n;
 			n.instance();
 			vnode = n;
-			seq_connect = true;
 		} else if (p_text == "VisualScriptSequence") {
 
 			Ref<VisualScriptSequence> n;
 			n.instance();
 			vnode = n;
-			seq_connect = true;
 		} else if (p_text == "VisualScriptIterator") {
 
 			Ref<VisualScriptIterator> n;
 			n.instance();
 			vnode = n;
-			seq_connect = true;
 		} else if (p_text == "VisualScriptWhile") {
 
 			Ref<VisualScriptWhile> n;
 			n.instance();
 			vnode = n;
-			seq_connect = true;
 		} else if (p_text == "VisualScriptReturn") {
 
 			Ref<VisualScriptReturn> n;
 			n.instance();
 			vnode = n;
-			seq_connect = true;
 		}
 	}
 
@@ -3489,7 +3479,6 @@ VisualScriptEditor::VisualScriptEditor() {
 		clipboard = memnew(Clipboard);
 	}
 	updating_graph = false;
-	seq_connect = false;
 
 	edit_menu = memnew(MenuButton);
 	edit_menu->set_text(TTR("Edit"));
diff --git a/modules/visual_script/visual_script_editor.h b/modules/visual_script/visual_script_editor.h
index 541ee941fb..fb90e346a4 100644
--- a/modules/visual_script/visual_script_editor.h
+++ b/modules/visual_script/visual_script_editor.h
@@ -160,8 +160,6 @@ class VisualScriptEditor : public ScriptEditorBase {
 	MemberType member_type;
 	String member_name;
 
-	bool seq_connect;
-
 	PortAction port_action;
 	int port_action_node;
 	int port_action_output;