GLES: Fixed build.

src/glimports.h

@@ -470,6 +470,8 @@ GL_IMPORT_____x(true,  PFNGLGETCOMPRESSEDTEXIMAGEPROC,             glGetCompress
 GL_IMPORT_____x(true,  PFNGLGETTEXIMAGEPROC,                       glGetTexImage);
 
 #	if BGFX_CONFIG_RENDERER_OPENGLES < 30
+GL_IMPORT______(true,  PFNGLGETSTRINGIPROC,                        glGetStringi);
+
 GL_IMPORT_OES__(true,  PFNGLTEXIMAGE3DPROC,                        glTexImage3D);
 GL_IMPORT_OES__(true,  PFNGLTEXSUBIMAGE3DPROC,                     glTexSubImage3D);
 GL_IMPORT_OES__(true,  PFNGLCOMPRESSEDTEXIMAGE3DPROC,              glCompressedTexImage3D);

src/renderer_gl.h

@@ -742,6 +742,10 @@ typedef uint64_t GLuint64;
 #	define GL_FRAMEBUFFER_SRGB 0x8DB9
 #endif // GL_FRAMEBUFFER_SRGB
 
+#ifndef GL_NUM_EXTENSIONS
+#	define GL_NUM_EXTENSIONS 0x821D
+#endif // GL_NUM_EXTENSIONS
+
 // _KHR or _ARB...
 #define GL_DEBUG_OUTPUT_SYNCHRONOUS         0x8242
 #define GL_DEBUG_NEXT_LOGGED_MESSAGE_LENGTH 0x8243