Revert of Change desktop and ES 3.0 to always use sized internal texture formats.

src/gpu/gl/GrGpuGL.cpp

Index: src/gpu/gl/GrGpuGL.cpp
diff --git a/src/gpu/gl/GrGpuGL.cpp b/src/gpu/gl/GrGpuGL.cpp
index e2ad556ffd62e9e491c5398727dd12314dfeccdb..a22988b01bbb8a117ea1262099dc8a934c076b25 100644
--- a/src/gpu/gl/GrGpuGL.cpp
+++ b/src/gpu/gl/GrGpuGL.cpp
@@ -558,10 +558,17 @@
     GrGLenum externalFormat = 0x0; // suprress warning
     GrGLenum externalType = 0x0;// suprress warning
 
-    // glTexStorage requires sized internal formats on both desktop and ES.
-    // ES2 requires an unsized format for glTexImage. On ES3 and desktop we default to sized.
-    bool useSizedFormat = useTexStorage || kGL_GrGLStandard == this->glStandard() ||
-                          this->glVersion() >= GR_GL_VER(3, 0);
+    // glTexStorage requires sized internal formats on both desktop and ES. ES2 requires an unsized
+    // format for glTexImage, unlike ES3 and desktop. However, we allow the driver to decide the
+    // size of the internal format whenever possible and so only use a sized internal format when
+    // using texture storage.
+    bool useSizedFormat = useTexStorage;
+    // Many versions of the ES3 drivers on various platforms will not accept GL_RED in
+    // glTexImage2D for the internal format but will accept GL_R8.
+    if (kGLES_GrGLStandard == this->glStandard() && this->glVersion() >= GR_GL_VER(3, 0) &&
+        kAlpha_8_GrPixelConfig == dataConfig) {
+        useSizedFormat = true;
+    }
     if (!this->configToGLFormats(dataConfig, useSizedFormat, &internalFormat,
                                  &externalFormat, &externalType)) {
         return false;