[sql] Rewrite sqlite patching "system".

third_party/sqlite/separate_cache_pool.patch

Index: third_party/sqlite/separate_cache_pool.patch
diff --git a/third_party/sqlite/separate_cache_pool.patch b/third_party/sqlite/separate_cache_pool.patch
deleted file mode 100644
index cf22f355ff0da15c329251d94446f3e34a368db8..0000000000000000000000000000000000000000
--- a/third_party/sqlite/separate_cache_pool.patch
+++ /dev/null
@@ -1,29 +0,0 @@
-diff --git src/pcache1.c src/pcache1.c
-index ad44395..e4d0705 100644
---- src/pcache1.c
-+++ src/pcache1.c
-@@ -549,10 +549,12 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
-   int sz;               /* Bytes of memory required to allocate the new cache */
- 
-   /*
--  ** The seperateCache variable is true if each PCache has its own private
-+  ** The separateCache variable is true if each PCache has its own private
-   ** PGroup.  In other words, separateCache is true for mode (1) where no
-   ** mutexing is required.
-   **
-+  **   *  Always use separate caches (mode-1) if SQLITE_SEPARATE_CACHE_POOLS
-+  **
-   **   *  Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
-   **
-   **   *  Always use a unified cache in single-threaded applications
-@@ -560,7 +562,9 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
-   **   *  Otherwise (if multi-threaded and ENABLE_MEMORY_MANAGEMENT is off)
-   **      use separate caches (mode-1)
-   */
--#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
-+#ifdef SQLITE_SEPARATE_CACHE_POOLS
-+  const int separateCache = 1;
-+#elif defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
-   const int separateCache = 0;
- #else
-   int separateCache = sqlite3GlobalConfig.bCoreMutex>0;