Revert "Make the default framebuffer owned by Surface"

This reverts commit 87e63a9982803b5e4c12afa9a40ff0e2b04a7369.

Speculative revert to fix the webgl cts on Windows D3D9 and the
unittests on Linux.

BUG=

Change-Id: I488f4e0b2dc67270eed45f1c10bfba1d13c98739
Reviewed-on: https://chromium-review.googlesource.com/293350
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/libANGLE/validationES.cpp b/src/libANGLE/validationES.cpp
index de7fcd5..a7804cf 100644
--- a/src/libANGLE/validationES.cpp
+++ b/src/libANGLE/validationES.cpp
@@ -605,7 +605,7 @@
             GLenum readInternalFormat = readColorBuffer->getInternalFormat();
             const InternalFormat &readFormatInfo = GetInternalFormatInfo(readInternalFormat);
 
-            for (int i = 0; i < drawFramebuffer->getNumColorBuffers(); i++)
+            for (GLuint i = 0; i < context->getCaps().maxColorAttachments; i++)
             {
                 if (drawFramebuffer->isEnabledColorAttachment(i))
                 {
@@ -661,8 +661,7 @@
                     return false;
                 }
 
-                for (int colorAttachment = 0;
-                     colorAttachment < drawFramebuffer->getNumColorBuffers(); ++colorAttachment)
+                for (GLuint colorAttachment = 0; colorAttachment < context->getCaps().maxColorAttachments; ++colorAttachment)
                 {
                     if (drawFramebuffer->isEnabledColorAttachment(colorAttachment))
                     {