Revert of Defer glClear to just before draw call (patchset #2 id:20001 of https://codereview.chromium.org/1113003005/)

Reason for revert:
This CL seems to be triggering the assert:
src/gpu/SkGpuDevice.cpp:319: failed assertion "!fNeedClear"
on, at least, Mac & Ubuntu.

Original issue's description:
> Defer glClear to just before draw call
>
> Remove some DO_DEFERRED_CLEAR call to avoid call glClear separately, like this:
> glBindFramebuffer(1)
> glClear
> glBindFramebuffer(2)
> glClear
> glBindFramebuffer(1)
> glDrawXXX
> glBindFramebuffer(2)
> glDrawXXX
>
> These call sequences may need read and write memory back and forth.
>
> If we call DO_DEFERRED_CLEAR just before draw call, we can bind, clear and draw in one go.
> e.g.
> glBindFramebuffer(1)
> glClear
> glDrawXXX
> glBindFramebuffer(2)
> glClear
> glDrawXXX
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/c3c06a13e69b90d4cc1d543853504072d363ae8b

TBR=bsalomon@google.com,joel.liang@arm.com,wasim.abbas@arm.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1136393005
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index e4c21ca..7b36363 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -62,7 +62,6 @@
 // a sub region of a larger source image.
 #define COLOR_BLEED_TOLERANCE 0.001f
 
-// Do deferred clear just before any draw call
 #define DO_DEFERRED_CLEAR()             \
     do {                                \
         if (fNeedClear) {               \
@@ -303,6 +302,7 @@
 }
 
 GrRenderTarget* SkGpuDevice::accessRenderTarget() {
+    DO_DEFERRED_CLEAR();
     return fRenderTarget;
 }