Add GL_OES_EGL_image functions.

Needed to work on Chrome OS.

BUG=angleproject:1297

Change-Id: I78e18472780745f73257c8954f263d236ff92180
Reviewed-on: https://chromium-review.googlesource.com/323470
Tryjob-Request: Frank Henigman <fjhenigman@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Frank Henigman <fjhenigman@chromium.org>
diff --git a/src/libANGLE/renderer/gl/FunctionsGL.cpp b/src/libANGLE/renderer/gl/FunctionsGL.cpp
index d4f401b..78d77ab 100644
--- a/src/libANGLE/renderer/gl/FunctionsGL.cpp
+++ b/src/libANGLE/renderer/gl/FunctionsGL.cpp
@@ -762,7 +762,9 @@
       vertexArrayVertexBuffer(nullptr),
       vertexArrayVertexBuffers(nullptr),
       blendBarrier(nullptr),
-      primitiveBoundingBox(nullptr)
+      primitiveBoundingBox(nullptr),
+      eglImageTargetRenderbufferStorageOES(nullptr),
+      eglImageTargetTexture2DOES(nullptr)
 {
 }
 
@@ -1772,6 +1774,10 @@
     AssignGLExtensionEntryPoint(extensions, "GL_EXT_occlusion_query_boolean", loadProcAddress("glGetQueryivEXT"), &getQueryiv);
     AssignGLExtensionEntryPoint(extensions, "GL_EXT_occlusion_query_boolean", loadProcAddress("glGetQueryObjectuivEXT"), &getQueryObjectuiv);
 
+    // GL_OES_EGL_image
+    AssignGLExtensionEntryPoint(extensions, "GL_OES_EGL_image", loadProcAddress("glEGLImageTargetRenderbufferStorageOES"), &eglImageTargetRenderbufferStorageOES);
+    AssignGLExtensionEntryPoint(extensions, "GL_OES_EGL_image", loadProcAddress("glEGLImageTargetTexture2DOES"), &eglImageTargetTexture2DOES);
+
     // 2.0
     if (isAtLeastGLES(gl::Version(2, 0)))
     {