Fix componene debug build failure in chromium

The error log is as follows:
../../third_party/skia/include/core/SkSpinlock.h:24: error: undefined reference to 'SkPODSpinlock::contendedAcquire()'
collect2: error: ld returned 1 exit status

[mtklein added below here]
Despite the presence in include/ and the added SK_API, this file is not part of Skia's public API... it's just used by files which are.
TBR=reed@google.com

Review URL: https://codereview.chromium.org/1229003004

diff --git a/include/core/SkSpinlock.h b/include/core/SkSpinlock.h
index 6edfdf0..82a2841 100644 (file)
--- a/include/core/SkSpinlock.h
+++ b/include/core/SkSpinlock.h
@@ -15,7 +15,7 @@
 #define SK_DECLARE_STATIC_SPINLOCK(name) namespace {} static SkPODSpinlock name
 
 // This class has no constructor and must be zero-initialized (the macro above does this).
-class SkPODSpinlock {
+class SK_API SkPODSpinlock {
 public:
     void acquire() {
         // To act as a mutex, we need an acquire barrier if we take the lock.