PyGPU: call 'GPU_shader_bind' in 'GPUShader.uniform_' methods

This simplifies python code.

When we call a method like shader.uniform_float("color", (1,1,1,1)),
we expect the shader's uniform to be updated regardless of whether the
shader is bound or not.

And `batch.draw()` already calls `GPU_shader_bind` inside.

Differential Revision: https://developer.blender.org/D15929

release/scripts/modules/bpy_types.py

@@ -742,7 +742,6 @@ class Gizmo(StructRNA):
             matrix = self.matrix_world
 
         batch, shader = shape
-        shader.bind()
 
         if select_id is not None:
             gpu.select.load_id(select_id)

release/scripts/modules/gpu_extras/presets.py

@@ -78,7 +78,6 @@ def draw_texture_2d(texture, position, width, height):
         gpu.matrix.scale((width, height))
 
         shader = gpu.shader.from_builtin('IMAGE')
-        shader.bind()
 
         if isinstance(texture, int):
             # Call the legacy bgl to not break the existing API

release/scripts/templates_py/operator_modal_draw.py

@@ -19,7 +19,6 @@ def draw_callback_px(self, context):
     gpu.state.blend_set('ALPHA')
     gpu.state.line_width_set(2.0)
     batch = batch_for_shader(shader, 'LINE_STRIP', {"pos": self.mouse_path})
-    shader.bind()
     shader.uniform_float("color", (0.0, 0.0, 0.0, 0.5))
     batch.draw(shader)