Revert of DM::SKPSrc::size() reports correct size. (patchset #3 id:40001 of https://codereview.chromium.org/863243005/)

Reason for revert:
Still no good on Chrome OS bot:

http://build.chromium.org/p/client.skia/builders/Test-ChromeOS-Alex-GMA3150-x86-Release/builds/628/steps/dm/logs/stdio

Original issue's description:
> DM::SKPSrc::size() reports correct size.
>
> Also, DM::GPUSink and DM::RasterSink crop DM::Src::size() to 2048x2048.
>
> Motivation:
>   Improve PDF testing by printing the entire SKP.
>
> Source: http://crrev.com/863243004
>
> BUG=skia:3365
>
> Committed: https://skia.googlesource.com/skia/+/441b10eac09a1f44983e35da827a6b438a409e63
>
> CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu12-ShuttleA-GTX660-x86-Release-Trybot,Test-ChromeOS-Alex-GMA3150-x86-Release-Trybot
>
> Committed: https://skia.googlesource.com/skia/+/d4dd58e43ca4551531ad6a9f54bfc5632ea45a80

TBR=halcanary@google.com,mtklein@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:3365

Review URL: https://codereview.chromium.org/886543005
diff --git a/gm/gm.h b/gm/gm.h
index 0de9875..b474729 100644
--- a/gm/gm.h
+++ b/gm/gm.h
@@ -53,14 +53,7 @@
         void drawBackground(SkCanvas*);
         void drawContent(SkCanvas*);
 
-        SkISize getISize() {
-            SkISize size = this->onISize();
-            // Sanity cap on GM dimensions.
-            SkASSERT(size.width() * size.height() <= 2359296 &&  // 2.25 megapixels
-                     size.width()                 <= 2048    &&  // Typical GPU max dimension.
-                     size.height()                <= 2048);
-            return size;
-        }
+        SkISize getISize() { return this->onISize(); }
         const char* getName();
 
         virtual bool runAsBench() const { return false; }