Add define to limit recommended offscreen allocations. This avoids some failures

skia/ext/bitmap_platform_device.h

Index: skia/ext/bitmap_platform_device.h
===================================================================
--- skia/ext/bitmap_platform_device.h	(revision 156622)
+++ skia/ext/bitmap_platform_device.h	(working copy)
@@ -18,4 +18,19 @@
 #include "skia/ext/bitmap_platform_device_linux.h"
 #endif
 
+namespace skia {
+    // Returns true if it is unsafe to attempt to allocate an offscreen buffer
+    // given these dimensions.
+    inline bool RasterDeviceTooBigToAllocate(int width, int height) {
+
+#ifndef SKIA_EXT_RASTER_DEVICE_ALLOCATION_MAX
+#define SKIA_EXT_RASTER_DEVICE_ALLOCATION_MAX    (256 * 1024 * 1024)

[Stephen White, 2012/09/14 21:01:33]

Just as a reference, canvas's hardcoded limit is 256MPixels, or ~1GB. Maybe we
should do the same?  64Mpixels might be a tad small for desktop (with hidpi and
all).

+#endif
+
+    int bytesPerPixel = 4;
+    int64_t bytes = (int64_t)width * height * bytesPerPixel;
+    return bytes > SKIA_EXT_RASTER_DEVICE_ALLOCATION_MAX;
+  }
+}
+
 #endif  // SKIA_EXT_BITMAP_PLATFORM_DEVICE_H_