Convert sqlite3PagerGet() into a pointer-dispatched virtual method. This

makes it about 25% faster.

FossilOrigin-Name: 7f88bb44129a0cd36e27e00dc7c37e87cf3c90f7

diff --cc manifest
index acf36f3b9329f61fa6aabe96faad3969aa776313,a735100eb089d871034d8c582fc2a29e6306f4c4..6c25d39d50b56a33eb6a703038df0930fd4a6217
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,5 -1,5 +1,5 @@@
- C Fix\sa\sproblem\scausing\sSQLite\sto\sreturn\sfalse\s"foreign\skey\sviolation"\serrors\nwhen\sthere\sis\sa\spartial\s(i.e.\sWHERE\sconstrained)\sUNIQUE\sindex\son\sthe\sparent\nkey\scolumns.\sThis\sbug\sdid\snot\scause\sSQLite\sto\sallow\sillegal\sdata\sto\sbe\ninserted\sinto\sthe\sdatabase,\sonly\sto\sreject\slegal\soperations.
- D 2016-12-13T16:57:49.299
 -C In\sthe\spager,\savoid\schecking\sfor\sthe\sillegal\spage\snumber\s0\sexcept\swhen\screating\na\snew\spage.
 -D 2016-12-13T18:34:01.957
++C Convert\ssqlite3PagerGet()\sinto\sa\spointer-dispatched\svirtual\smethod.\s\sThis\nmakes\sit\sabout\s25%\sfaster.
++D 2016-12-13T18:47:54.625
  F Makefile.in 7639c6a09da11a9c7c6f2630fc981ee588d1072d
  F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
  F Makefile.msc b8ca53350ae545e3562403d5da2a69cec79308da
@@@ -375,10 -375,10 +375,10 @@@ F src/os_setup.h 0dbaea40a7d36bf311613d
  F src/os_unix.c 30e2c43e4955db990e5b5a81e901f8aa74cc8820
  F src/os_win.c cf90abd4e50d9f56d2c20ce8e005aff55d7bd8e9
  F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
- F src/pager.c eaf8590131ab651420e86e89c3fd12d729f55ad3
 -F src/pager.c 38b3a02f5f5e49224a006d17c842c106a93cb5b9
++F src/pager.c dbcac003871bf8a9bfb69d6cb66bbb85b528aaf6
  F src/pager.h d1e944291030351f362a0a7da9b5c3e34e603e39
  F src/parse.y 29153738a7322054359320eb00b5a4cd44389f20
- F src/pcache.c 219fc5238d5c80e2990ab01e1459db3a96866447
+ F src/pcache.c 51070ec9b8251bbf9c6ea3d35fd96a458752929e
  F src/pcache.h 2cedcd8407eb23017d92790b112186886e179490
  F src/pcache1.c e3967219b2a92b9edcb9324a4ba75009090d3953
  F src/pragma.c d932ba278654617cdd281f88a790a3185fca7c44
@@@ -1536,7 -1536,7 +1536,8 @@@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a9
  F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
  F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
  F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
- P 1a636d5e0eec0a4d968519d1dfd35a983e512c78
- R 5a6882353526d0c1387fb8d5e18f94f5
- U dan
- Z 8572282c856eadf1ae5a34d00073243b
 -P 67df44464847b43f8c0b186157e31cc66c1e5796
 -R 96cb62ad3fe18d08872a93c1ec7681b1
++P 850877d1ea43104cc215353414b870c340acced2 dee20ba982125ea98c280ad1571789af0f393903
++R 1925a57b32b9d19fb42c95ae0d5863ee
++T +closed dee20ba982125ea98c280ad1571789af0f393903
+ U drh
 -Z 5d3a5e7b85c439c40dd9c8767b987c29
++Z ca81384c708270e6307c733a622217dc

diff --cc manifest.uuid
index 5e21fc481638b7af4ba513a30a36901e31a14a08,e5fa81fb64ac4a0d5cb898c4e79ad672db5b342d..ad8184c8edb0ef76ed721279c84d4accb41dd12a
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- 850877d1ea43104cc215353414b870c340acced2
 -dee20ba982125ea98c280ad1571789af0f393903
++7f88bb44129a0cd36e27e00dc7c37e87cf3c90f7

diff --cc src/pager.c
index 02e9aac7904221d913e50c2198b34c9995bc53d0,d40c1f4117c541bd1ac7d458298533148e862397..7bafc1c09ba9a86ff6935e56906d060e2cdbe51e
--- 1/src/pager.c
--- 2/src/pager.c
+++ b/src/pager.c
@@@ -6721,6 -6791,7 +6791,7 @@@ int sqlite3PagerSavepoint(Pager *pPager
      ){
        pPager->errCode = SQLITE_ABORT;
        pPager->eState = PAGER_ERROR;
 -      setGettterMethod(pPager);
++      setGetterMethod(pPager);
      }
  #endif
    }