lossless: fix crunch mode w/WEBP_REDUCE_SIZE

WEBP_REDUCE_SIZE was introduced to bring down the library size by
removing cropping and scaling support. Previously WebPPictureView() was
only used with these two, but in
  ec178f2c Add progress hook granularity in lossless
an additional use was added in VP8LEncodeStream() when extra side
configurations are used in crunch mode (-mt, quality == 100 & method ==
6 or quality >= 75 & method == 5 with a palette present currently).

WebPPictureView() and, for coherency, WebPPictureIsView() are
restored in this configuration to avoid affecting the general encode
path.

Previously WebPPictureView() was assumed to always succeed in these
cases which could result in crashes with WEBP_REDUCE_SIZE defined.

Bug: chromium:1345547
Bug: chromium:1345595
Bug: chromium:1345772
Bug: chromium:1345804
Change-Id: Ifecde36a726a434510478a764514b1469942c684
(cherry picked from commit 84163d9d02)

CMakeLists.txt

@@ -509,18 +509,19 @@ endif()
 
 if(WEBP_BUILD_LIBWEBPMUX)
   parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/src/mux "WEBP_MUX_SRCS" "")
-  add_library(webpmux ${WEBP_MUX_SRCS})
-  target_link_libraries(webpmux webp)
-  target_include_directories(webpmux
+  add_library(libwebpmux ${WEBP_MUX_SRCS})
+  target_link_libraries(libwebpmux webp)
+  target_include_directories(libwebpmux
                              PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
                                      ${CMAKE_CURRENT_SOURCE_DIR})
-  set_version(mux/Makefile.am webpmux webpmux)
-  set_target_properties(webpmux
+  set_version(mux/Makefile.am libwebpmux webpmux)
+  set_target_properties(libwebpmux
                         PROPERTIES PUBLIC_HEADER
                                    "${CMAKE_CURRENT_SOURCE_DIR}/src/webp/mux.h;\
 ${CMAKE_CURRENT_SOURCE_DIR}/src/webp/mux_types.h;\
 ${CMAKE_CURRENT_SOURCE_DIR}/src/webp/types.h;")
-  list(APPEND INSTALLED_LIBRARIES webpmux)
+  set_target_properties(libwebpmux PROPERTIES OUTPUT_NAME webpmux)
+  list(APPEND INSTALLED_LIBRARIES libwebpmux)
   configure_pkg_config("src/mux/libwebpmux.pc")
 endif()
 
@@ -534,7 +535,7 @@ if(WEBP_BUILD_GIF2WEBP)
                         exampleutil
                         imageioutil
                         webp
-                        webpmux
+                        libwebpmux
                         ${WEBP_DEP_GIF_LIBRARIES})
   target_include_directories(gif2webp PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
   install(TARGETS gif2webp RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
@@ -551,7 +552,7 @@ if(WEBP_BUILD_IMG2WEBP)
                         imagedec
                         imageioutil
                         webp
-                        webpmux)
+                        libwebpmux)
   target_include_directories(img2webp PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
   install(TARGETS img2webp RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 endif()
@@ -601,12 +602,10 @@ if(WEBP_BUILD_WEBPMUX)
   # webpmux
   parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "WEBPMUX_SRCS"
                     "webpmux")
-  add_executable(webpmux_app ${WEBPMUX_SRCS})
-  set_target_properties(webpmux_app PROPERTIES OUTPUT_NAME webpmux)
-  target_link_libraries(webpmux_app exampleutil imageioutil webpmux webp)
-  target_include_directories(webpmux_app
-                             PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
-  install(TARGETS webpmux_app RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+  add_executable(webpmux ${WEBPMUX_SRCS})
+  target_link_libraries(webpmux exampleutil imageioutil libwebpmux webp)
+  target_include_directories(webpmux PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+  install(TARGETS webpmux RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 endif()
 
 if(WEBP_BUILD_EXTRAS)
@@ -738,6 +737,10 @@ write_basic_package_version_file(
 
 # Create the Config file.
 include(CMakePackageConfigHelpers)
+# Fix libwebpmux reference. The target name libwebpmux is used for
+# compatibility purposes, but the library mentioned in WebPConfig.cmake should
+# be the unprefixed version.
+list(TRANSFORM INSTALLED_LIBRARIES REPLACE "libwebpmux" "webpmux")
 configure_package_config_file(
   ${CMAKE_CURRENT_SOURCE_DIR}/cmake/WebPConfig.cmake.in
   ${CMAKE_CURRENT_BINARY_DIR}/WebPConfig.cmake

src/enc/picture_rescale_enc.c

@@ -13,14 +13,15 @@
 
 #include "src/webp/encode.h"
 
-#if !defined(WEBP_REDUCE_SIZE)
-
 #include <assert.h>
 #include <stdlib.h>
 
 #include "src/enc/vp8i_enc.h"
+
+#if !defined(WEBP_REDUCE_SIZE)
 #include "src/utils/rescaler_utils.h"
 #include "src/utils/utils.h"
+#endif  // !defined(WEBP_REDUCE_SIZE)
 
 #define HALVE(x) (((x) + 1) >> 1)
 
@@ -56,6 +57,7 @@ static int AdjustAndCheckRectangle(const WebPPicture* const pic,
   return 1;
 }
 
+#if !defined(WEBP_REDUCE_SIZE)
 int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst) {
   if (src == NULL || dst == NULL) return 0;
   if (src == dst) return 1;
@@ -81,6 +83,7 @@ int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst) {
   }
   return 1;
 }
+#endif  // !defined(WEBP_REDUCE_SIZE)
 
 int WebPPictureIsView(const WebPPicture* picture) {
   if (picture == NULL) return 0;
@@ -120,6 +123,7 @@ int WebPPictureView(const WebPPicture* src,
   return 1;
 }
 
+#if !defined(WEBP_REDUCE_SIZE)
 //------------------------------------------------------------------------------
 // Picture cropping
 
@@ -277,23 +281,6 @@ int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst) {
   return 0;
 }
 
-int WebPPictureIsView(const WebPPicture* picture) {
-  (void)picture;
-  return 0;
-}
-
-int WebPPictureView(const WebPPicture* src,
-                    int left, int top, int width, int height,
-                    WebPPicture* dst) {
-  (void)src;
-  (void)left;
-  (void)top;
-  (void)width;
-  (void)height;
-  (void)dst;
-  return 0;
-}
-
 int WebPPictureCrop(WebPPicture* pic,
                     int left, int top, int width, int height) {
   (void)pic;