fix #if to #ifdef for SK_DEBUG

fix the chrome build

R=mtklein@google.com
TBR=mtklein
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/495453003
diff --git a/src/core/SkRecordDraw.cpp b/src/core/SkRecordDraw.cpp
index 613c2c0..a1c148a 100644
--- a/src/core/SkRecordDraw.cpp
+++ b/src/core/SkRecordDraw.cpp
@@ -312,13 +312,13 @@
     }
 
     static void AdjustTextForFontMetrics(SkRect* rect, const SkPaint& paint) {
-#if SK_DEBUG
+#ifdef SK_DEBUG
         SkRect correct = *rect;
 #endif
         const SkScalar yPad = 1.5f * paint.getTextSize(),  // In practice, this seems to be enough.
                        xPad = 4.0f * yPad;                 // Hack for very wide Github logo font.
         rect->outset(xPad, yPad);
-#if SK_DEBUG
+#ifdef SK_DEBUG
         SkPaint::FontMetrics metrics;
         paint.getFontMetrics(&metrics);
         correct.fLeft   += metrics.fXMin;