remove useless APIs in WGC3DImpl

BUG=

Review URL: https://codereview.chromium.org/898263002

Cr-Commit-Position: refs/heads/master@{#315268}

AUTHORS

@@ -520,6 +520,7 @@ Yoshinori Sano <yoshinori.sano@gmail.com>
 YoungKi Hong <simon.hong81@gmail.com>
 Youngsun Suh <zard17@gmail.com>
 Yumikiyo Osanai <yumios.art@gmail.com>
+Yunchao He <yunchao.he@intel.com>
 Yuri Gorobets <yuri.gorobets@gmail.com>
 Zeno Albisser <zeno.albisser@digia.com>
 Zhaoze Zhou <zhaoze.zhou@partner.samsung.com>

gpu/blink/webgraphicscontext3d_impl.cc

@@ -709,23 +709,6 @@ void WebGraphicsContext3DImpl::vertexAttribPointer(
 DELEGATE_TO_GL_4(viewport, Viewport,
                  WGC3Dint, WGC3Dint, WGC3Dsizei, WGC3Dsizei)
 
-DELEGATE_TO_GL_2(genBuffers, GenBuffers, WGC3Dsizei, WebGLId*);
-
-DELEGATE_TO_GL_2(genFramebuffers, GenFramebuffers, WGC3Dsizei, WebGLId*);
-
-DELEGATE_TO_GL_2(genRenderbuffers, GenRenderbuffers, WGC3Dsizei, WebGLId*);
-
-DELEGATE_TO_GL_2(genTextures, GenTextures, WGC3Dsizei, WebGLId*);
-
-DELEGATE_TO_GL_2(deleteBuffers, DeleteBuffers, WGC3Dsizei, WebGLId*);
-
-DELEGATE_TO_GL_2(deleteFramebuffers, DeleteFramebuffers, WGC3Dsizei, WebGLId*);
-
-DELEGATE_TO_GL_2(deleteRenderbuffers, DeleteRenderbuffers, WGC3Dsizei,
-                 WebGLId*);
-
-DELEGATE_TO_GL_2(deleteTextures, DeleteTextures, WGC3Dsizei, WebGLId*);
-
 WebGLId WebGraphicsContext3DImpl::createBuffer() {
   GLuint o;
   gl_->GenBuffers(1, &o);

gpu/blink/webgraphicscontext3d_impl.h

@@ -371,17 +371,6 @@ class GPU_BLINK_EXPORT WebGraphicsContext3DImpl
   virtual void viewport(WGC3Dint x, WGC3Dint y,
                         WGC3Dsizei width, WGC3Dsizei height);
 
-  // Support for buffer creation and deletion
-  virtual void genBuffers(WGC3Dsizei count, WebGLId* ids);
-  virtual void genFramebuffers(WGC3Dsizei count, WebGLId* ids);
-  virtual void genRenderbuffers(WGC3Dsizei count, WebGLId* ids);
-  virtual void genTextures(WGC3Dsizei count, WebGLId* ids);
-
-  virtual void deleteBuffers(WGC3Dsizei count, WebGLId* ids);
-  virtual void deleteFramebuffers(WGC3Dsizei count, WebGLId* ids);
-  virtual void deleteRenderbuffers(WGC3Dsizei count, WebGLId* ids);
-  virtual void deleteTextures(WGC3Dsizei count, WebGLId* ids);
-
   virtual WebGLId createBuffer();
   virtual WebGLId createFramebuffer();
   virtual WebGLId createRenderbuffer();