Check that IDirect3DVertexBuffer9 and IDirect3DIndexBuffer9::Lock succeed.

I've been seeing crashes like this on Windows XP:

0x013319aa 	[libglesv2.dll 	- memcpy.asm:188] 	memcpy
0x0130989a 	[libglesv2.dll 	- vertexdatamanager.cpp:164] 	gl::VertexDataManager::preRenderValidate(int,int,gl::TranslatedAttribute *)
0x01304f66 	[libglesv2.dll 	- context.cpp:1996] 	gl::Context::applyVertexBuffer(unsigned int,int,int,bool *,gl::TranslatedIndexData *)
0x013061a7 	[libglesv2.dll 	- context.cpp:2648] 	gl::Context::drawArrays(unsigned int,int,int)
0x012f7721 	[libglesv2.dll 	- libglesv2.cpp:1741] 	glDrawArrays
0x01c54f1e 	[chrome.dll 	- gles2_cmd_decoder.cc:3179] 	gpu::gles2::GLES2DecoderImpl::DoDrawArrays(unsigned int,int,int)
0x01c59122 	[chrome.dll 	- gles2_cmd_decoder_autogen.h:640] 	gpu::gles2::GLES2DecoderImpl::HandleDrawArrays(unsigned int,gpu::gles2::DrawArrays const &)

Review URL: http://codereview.appspot.com/3043042

git-svn-id: https://angleproject.googlecode.com/svn/trunk@480 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/geometry/IndexDataManager.cpp b/src/libGLESv2/geometry/IndexDataManager.cpp
index d573579..a8227a8 100644
--- a/src/libGLESv2/geometry/IndexDataManager.cpp
+++ b/src/libGLESv2/geometry/IndexDataManager.cpp
@@ -103,6 +103,11 @@
 
     size_t offset;
     void *output = streamIb->map(requiredSpace, &offset);
+    if (output == NULL)
+    {
+        ERR(" failed to map index buffer.");
+        return GL_OUT_OF_MEMORY;
+    }
 
     translated->buffer = streamIb;
     translated->offset = offset;
@@ -210,6 +215,11 @@
         mLineLoopBuffer = mBackend->createIndexBuffer((count+1) * sizeof(unsigned short), GL_UNSIGNED_SHORT);
 
         unsigned short *indices = static_cast<unsigned short *>(mLineLoopBuffer->map());
+        if (indices == NULL)
+        {
+            ERR(" failed to map index buffer.");
+            return GL_OUT_OF_MEMORY;
+        }
 
         for (int i = 0; i < count; i++)
         {
@@ -232,6 +242,11 @@
         mCountingBuffer = mBackend->createIndexBuffer(count * sizeof(unsigned short), GL_UNSIGNED_SHORT);
 
         unsigned short *indices = static_cast<unsigned short *>(mCountingBuffer->map());
+        if (indices == NULL)
+        {
+            ERR(" failed to map index buffer.");
+            return GL_OUT_OF_MEMORY;
+        }
 
         for (int i = 0; i < count; i++)
         {