Use precompiled headers for most large projects.

ppapi/proxy/ppapi_proxy_test.cc

Index: ppapi/proxy/ppapi_proxy_test.cc
diff --git a/ppapi/proxy/ppapi_proxy_test.cc b/ppapi/proxy/ppapi_proxy_test.cc
index eb7b440c273d273b7ed202542d577443c95b780f..8817091a29e46d139200188e69c25447533a63cf 100644
--- a/ppapi/proxy/ppapi_proxy_test.cc
+++ b/ppapi/proxy/ppapi_proxy_test.cc
@@ -63,9 +63,9 @@ const void* MockGetInterface(const char* name) {
   ObserverList<ProxyTestHarnessBase>::Iterator it =
       get_interface_handlers_;
   while (ProxyTestHarnessBase* observer = it.GetNext()) {
-    const void* interface = observer->GetInterface(name);
-    if (interface)
-      return interface;
+    const void* mock_interface = observer->GetInterface(name);
+    if (mock_interface)
+      return mock_interface;
   }
   if (strcmp(name, PPB_PROXY_PRIVATE_INTERFACE) == 0)
     return &ppb_proxy_private;
@@ -106,8 +106,8 @@ const void* ProxyTestHarnessBase::GetInterface(const char* name) {
 }
 
 void ProxyTestHarnessBase::RegisterTestInterface(const char* name,
-                                                 const void* interface) {
-  registered_interfaces_[name] = interface;
+                                                 const void* test_interface) {
+  registered_interfaces_[name] = test_interface;
 }
 
 bool ProxyTestHarnessBase::SupportsInterface(const char* name) {