Initial version of external_oes texture support and unit test

src/gpu/gl/angle/SkANGLEGLContext.cpp

Index: src/gpu/gl/angle/SkANGLEGLContext.cpp
diff --git a/src/gpu/gl/angle/SkANGLEGLContext.cpp b/src/gpu/gl/angle/SkANGLEGLContext.cpp
index 64a3bdec74381365db58936fe4d43db3a424bc16..54ef02d492468864f82ee60e89eba16120dabbe9 100644
--- a/src/gpu/gl/angle/SkANGLEGLContext.cpp
+++ b/src/gpu/gl/angle/SkANGLEGLContext.cpp
@@ -11,6 +11,9 @@
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
 
+#include "gl/GrGLDefines.h"
+#include "gl/GrGLUtil.h"
+
 #define EGL_PLATFORM_ANGLE_ANGLE                0x3202
 #define EGL_PLATFORM_ANGLE_TYPE_ANGLE           0x3203
 #define EGL_PLATFORM_ANGLE_TYPE_D3D9_ANGLE      0x3207
@@ -34,8 +37,7 @@ void* SkANGLEGLContext::GetD3DEGLDisplay(void* nativeDisplay, bool useGLBackend)
               EGL_PLATFORM_ANGLE_TYPE_OPENGL_ANGLE,
               EGL_NONE
         };
-        display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE,
-                                            nativeDisplay, attribs);
+        display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE, nativeDisplay, attribs);
     } else {
         // Try for an ANGLE D3D11 context, fall back to D3D9, and finally GL.
         EGLint attribs[3][3] = {
@@ -56,8 +58,7 @@ void* SkANGLEGLContext::GetD3DEGLDisplay(void* nativeDisplay, bool useGLBackend)
             }
         };
         for (int i = 0; i < 3 && display == EGL_NO_DISPLAY; ++i) {
-            display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE,
-                                                nativeDisplay, attribs[i]);
+            display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE,nativeDisplay, attribs[i]);
         }
     }
     return display;
@@ -79,6 +80,7 @@ SkANGLEGLContext::SkANGLEGLContext(bool useGLBackend)
         EGL_NONE
     };
 
+    fIsGLBackend = useGLBackend;
     fDisplay = GetD3DEGLDisplay(EGL_DEFAULT_DISPLAY, useGLBackend);
     if (EGL_NO_DISPLAY == fDisplay) {
         SkDebugf("Could not create EGL display!");
@@ -129,6 +131,62 @@ SkANGLEGLContext::~SkANGLEGLContext() {
     this->destroyGLContext();
 }
 
+GrEGLImage SkANGLEGLContext::texture2DToEGLImage(GrGLuint texID) const {
+    if (!this->gl()->hasExtension("EGL_KHR_gl_texture_2D_image")) {
+        return GR_EGL_NO_IMAGE;
+    }
+    GrEGLImage img;
+    GrEGLint attribs[] = { GR_EGL_GL_TEXTURE_LEVEL, 0,
+                           GR_EGL_IMAGE_PRESERVED, GR_EGL_TRUE,
+                           GR_EGL_NONE };
+    // 64 bit cast is to shut Visual C++ up about casting 32 bit value to a pointer.
+    GrEGLClientBuffer clientBuffer = reinterpret_cast<GrEGLClientBuffer>((uint64_t)texID);
+    GR_GL_CALL_RET(this->gl(), img,
+                   EGLCreateImage(fDisplay, fContext, GR_EGL_GL_TEXTURE_2D, clientBuffer,
+                                  attribs));
+    return img;
+}
+
+void SkANGLEGLContext::destroyEGLImage(GrEGLImage image) const {
+    GR_GL_CALL(this->gl(), EGLDestroyImage(fDisplay, image));
+}
+
+GrGLuint SkANGLEGLContext::eglImageToExternalTexture(GrEGLImage image) const {
+    GrGLClearErr(this->gl());
+    if (!this->gl()->hasExtension("GL_OES_EGL_image_external")) {
+        return 0;
+    }
+    GrGLEGLImageTargetTexture2DProc glEGLImageTargetTexture2D =
+        (GrGLEGLImageTargetTexture2DProc)eglGetProcAddress("glEGLImageTargetTexture2DOES");
+    if (!glEGLImageTargetTexture2D) {
+        return 0;
+    }
+    GrGLuint texID;
+    GR_GL_CALL(this->gl(), GenTextures(1, &texID));
+    if (!texID) {
+        return 0;
+    }
+    GR_GL_CALL(this->gl(), BindTexture(GR_GL_TEXTURE_EXTERNAL, texID));
+    if (GR_GL_GET_ERROR(this->gl()) != GR_GL_NO_ERROR) {
+        GR_GL_CALL(this->gl(), DeleteTextures(1, &texID));
+        return 0;
+    }
+    glEGLImageTargetTexture2D(GR_GL_TEXTURE_EXTERNAL, image);
+    if (GR_GL_GET_ERROR(this->gl()) != GR_GL_NO_ERROR) {
+        GR_GL_CALL(this->gl(), DeleteTextures(1, &texID));
+        return 0;
+    }
+    return texID;
+}
+
+SkGLContext* SkANGLEGLContext::createNew() const {
+    SkGLContext* ctx = SkANGLEGLContext::Create(this->gl()->fStandard, fIsGLBackend);
+    if (ctx) {
+        ctx->makeCurrent();
+    }
+    return ctx;
+}
+
 void SkANGLEGLContext::destroyGLContext() {
     if (fDisplay) {
         eglMakeCurrent(fDisplay, 0, 0, 0);