Revert of Improve GLSL integer support

src/gpu/gl/GrGLAssembleInterface.cpp

Index: src/gpu/gl/GrGLAssembleInterface.cpp
diff --git a/src/gpu/gl/GrGLAssembleInterface.cpp b/src/gpu/gl/GrGLAssembleInterface.cpp
index e52d302190d099e8e6c03e0fec17ff153ad898ee..30eed62c5e49f05387a21117e492d647919a1145 100644
--- a/src/gpu/gl/GrGLAssembleInterface.cpp
+++ b/src/gpu/gl/GrGLAssembleInterface.cpp
@@ -244,10 +244,6 @@
 
     if (glVer >= GR_GL_VER(3,2) || extensions.has("GL_ARB_instanced_arrays")) {
         GET_PROC(VertexAttribDivisor);
-    }
-
-    if (glVer >= GR_GL_VER(3,0)) {
-        GET_PROC(VertexAttribIPointer);
     }
 
     GET_PROC(VertexAttribPointer);
@@ -682,10 +678,6 @@
         GET_PROC_SUFFIX(VertexAttribDivisor, EXT);
     }
 
-    if (version >= GR_GL_VER(3,0)) {
-        GET_PROC(VertexAttribIPointer);
-    }
-
     GET_PROC(VertexAttribPointer);
     GET_PROC(Viewport);
     GET_PROC(BindFramebuffer);