GN: default to -O1

src/core/SkGlyphCache.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGlyphCache.h"
 #include "SkGlyphCache_Globals.h"
 #include "SkGraphics.h"
@@ skipping 527 matching lines @@
                                        const SkDescriptor* desc,
                                        bool (*proc)(const SkGlyphCache*, void*),
                                        void* context) {
     if (!typeface) {
         typeface = SkTypeface::GetDefaultTypeface();
     }
     SkASSERT(desc);
 
     // Precondition: the typeface id must be the fFontID in the descriptor
     SkDEBUGCODE(
-        uint32_t length;
+        uint32_t length = 0;
         const SkScalerContext::Rec* rec = static_cast<const SkScalerContext::Rec*>(
             desc->findEntry(kRec_SkDescriptorTag, &length));
         SkASSERT(rec);
         SkASSERT(length == sizeof(*rec));
         SkASSERT(typeface->uniqueID() == rec->fFontID);
     )
 
     SkGlyphCache_Globals& globals = get_globals();
     SkGlyphCache*         cache;
 
@@ skipping 291 matching lines @@
 }
 
 void SkGraphics::PurgeFontCache() {
     get_globals().purgeAll();
     SkTypefaceCache::PurgeAll();
 }
 
 // TODO(herb): clean up TLS apis.
 size_t SkGraphics::GetTLSFontCacheLimit() { return 0; }
 void SkGraphics::SetTLSFontCacheLimit(size_t bytes) { }