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 30eed62c5e49f05387a21117e492d647919a1145..e52d302190d099e8e6c03e0fec17ff153ad898ee 100644
--- a/src/gpu/gl/GrGLAssembleInterface.cpp
+++ b/src/gpu/gl/GrGLAssembleInterface.cpp
@@ -246,6 +246,10 @@ const GrGLInterface* GrGLAssembleGLInterface(void* ctx, GrGLGetProc get) {
         GET_PROC(VertexAttribDivisor);
     }
 
+    if (glVer >= GR_GL_VER(3,0)) {
+        GET_PROC(VertexAttribIPointer);
+    }
+
     GET_PROC(VertexAttribPointer);
     GET_PROC(Viewport);
     GET_PROC(BindFragDataLocationIndexed);
@@ -678,6 +682,10 @@ const GrGLInterface* GrGLAssembleGLESInterface(void* ctx, GrGLGetProc get) {
         GET_PROC_SUFFIX(VertexAttribDivisor, EXT);
     }
 
+    if (version >= GR_GL_VER(3,0)) {
+        GET_PROC(VertexAttribIPointer);
+    }
+
     GET_PROC(VertexAttribPointer);
     GET_PROC(Viewport);
     GET_PROC(BindFramebuffer);